From 3ddfaebd434d94f54c06ee6eae3f64d0150373d9 Mon Sep 17 00:00:00 2001
From: raortegar <raquel.ortega@moodle.com>
Date: Wed, 22 Mar 2023 12:53:16 +0100
Subject: [PATCH] MDL-76800 lib: upgrade OpenSpout to 4.0

---
 lib/openspout/README.md                       |  34 +-
 .../src/Autoloader/Psr4Autoloader.php         | 147 -------
 lib/openspout/src/Autoloader/autoload.php     |  15 -
 .../src/Common/Creator/HelperFactory.php      |  48 ---
 lib/openspout/src/Common/Entity/Cell.php      | 232 ++---------
 .../src/Common/Entity/Cell/BooleanCell.php    |  24 ++
 .../Common/Entity/Cell/DateIntervalCell.php   |  25 ++
 .../src/Common/Entity/Cell/DateTimeCell.php   |  25 ++
 .../src/Common/Entity/Cell/EmptyCell.php      |  24 ++
 .../src/Common/Entity/Cell/ErrorCell.php      |  29 ++
 .../src/Common/Entity/Cell/FormulaCell.php    |  24 ++
 .../src/Common/Entity/Cell/NumericCell.php    |  24 ++
 .../src/Common/Entity/Cell/StringCell.php     |  24 ++
 .../src/Common/Entity/Comment/Comment.php     |  47 +++
 .../src/Common/Entity/Comment/TextRun.php     |  23 ++
 lib/openspout/src/Common/Entity/Row.php       | 132 +++---
 .../src/Common/Entity/Style/Border.php        |  68 +---
 .../src/Common/Entity/Style/BorderPart.php    | 191 +++------
 .../src/Common/Entity/Style/CellAlignment.php |  12 +-
 .../Entity/Style/CellVerticalAlignment.php    |  37 ++
 .../src/Common/Entity/Style/Color.php         |  20 +-
 .../src/Common/Entity/Style/Style.php         | 364 +++++++----------
 .../Exception/EncodingConversionException.php |   4 +-
 .../src/Common/Exception/IOException.php      |   4 +-
 .../Exception/InvalidArgumentException.php    |   4 +-
 .../Exception/InvalidColorException.php       |   4 +-
 .../Common/Exception/OpenSpoutException.php   |  11 +
 .../src/Common/Exception/SpoutException.php   |   7 -
 .../Exception/UnsupportedTypeException.php    |   4 +-
 .../src/Common/Helper/CellTypeHelper.php      |  82 ----
 .../src/Common/Helper/EncodingHelper.php      | 119 +++---
 .../src/Common/Helper/Escaper/CSV.php         |  37 --
 .../Helper/Escaper/EscaperInterface.php       |   8 +-
 .../src/Common/Helper/Escaper/ODS.php         |  42 +-
 .../src/Common/Helper/Escaper/XLSX.php        |  40 +-
 .../src/Common/Helper/FileSystemHelper.php    |  74 ++--
 .../Helper/FileSystemHelperInterface.php      |  21 +-
 .../Common/Helper/GlobalFunctionsHelper.php   | 371 -----------------
 .../src/Common/Helper/StringHelper.php        |  79 ++--
 .../Common/Manager/OptionsManagerAbstract.php |  82 ----
 .../Manager/OptionsManagerInterface.php       |  31 --
 .../src/Common/TempFolderOptionTrait.php      |  33 ++
 lib/openspout/src/Common/Type.php             |  13 -
 ...{ReaderAbstract.php => AbstractReader.php} | 147 ++-----
 .../CSV/Creator/InternalEntityFactory.php     |  98 -----
 .../src/Reader/CSV/Manager/OptionsManager.php |  39 --
 lib/openspout/src/Reader/CSV/Options.php      |  15 +
 lib/openspout/src/Reader/CSV/Reader.php       | 132 ++----
 lib/openspout/src/Reader/CSV/RowIterator.php  | 116 ++----
 lib/openspout/src/Reader/CSV/Sheet.php        |  30 +-
 .../src/Reader/CSV/SheetIterator.php          |  26 +-
 .../src/Reader/Common/ColumnWidth.php         |  22 +
 .../InternalEntityFactoryInterface.php        |  26 --
 .../Common/Creator/ReaderEntityFactory.php    |  72 ----
 .../Reader/Common/Creator/ReaderFactory.php   |  95 ++---
 .../src/Reader/Common/Entity/Options.php      |  22 -
 .../src/Reader/Common/Manager/RowManager.php  |  47 +--
 .../src/Reader/Common/XMLProcessor.php        |  43 +-
 .../Exception/InvalidValueException.php       |  19 +-
 .../IteratorNotRewindableException.php        |   4 +-
 .../Exception/NoSheetsFoundException.php      |   4 +-
 .../src/Reader/Exception/ReaderException.php  |   6 +-
 .../Exception/ReaderNotOpenedException.php    |   4 +-
 .../SharedStringNotFoundException.php         |   4 +-
 .../Exception/XMLProcessingException.php      |   4 +-
 .../src/Reader/IteratorInterface.php          |  14 -
 .../src/Reader/ODS/Creator/HelperFactory.php  |  43 --
 .../ODS/Creator/InternalEntityFactory.php     | 124 ------
 .../src/Reader/ODS/Creator/ManagerFactory.php |  21 -
 .../Reader/ODS/Helper/CellValueFormatter.php  | 166 ++++----
 .../src/Reader/ODS/Helper/SettingsHelper.php  |  29 +-
 .../src/Reader/ODS/Manager/OptionsManager.php |  32 --
 lib/openspout/src/Reader/ODS/Options.php      |  11 +
 lib/openspout/src/Reader/ODS/Reader.php       |  64 ++-
 lib/openspout/src/Reader/ODS/RowIterator.php  | 145 +++----
 lib/openspout/src/Reader/ODS/Sheet.php        |  38 +-
 .../src/Reader/ODS/SheetIterator.php          | 124 +++---
 lib/openspout/src/Reader/ReaderInterface.php  |  14 +-
 .../src/Reader/RowIteratorInterface.php       |  18 +-
 lib/openspout/src/Reader/SheetInterface.php   |  19 +-
 .../src/Reader/SheetIteratorInterface.php     |  19 +-
 .../Reader/SheetWithVisibilityInterface.php   |  18 +
 .../Wrapper/XMLInternalErrorsHelper.php       |  20 +-
 .../src/Reader/Wrapper/XMLReader.php          |  54 +--
 .../src/Reader/XLSX/Creator/HelperFactory.php |  38 --
 .../XLSX/Creator/InternalEntityFactory.php    | 163 --------
 .../Reader/XLSX/Creator/ManagerFactory.php    | 109 -----
 .../src/Reader/XLSX/Helper/CellHelper.php     |  28 +-
 .../Reader/XLSX/Helper/CellValueFormatter.php | 189 ++++-----
 .../Reader/XLSX/Helper/DateFormatHelper.php   |  25 +-
 .../Reader/XLSX/Manager/OptionsManager.php    |  36 --
 .../CachingStrategyFactory.php                |  76 +---
 .../CachingStrategyInterface.php              |  16 +-
 .../FileBasedStrategy.php                     |  97 +++--
 .../SharedStringsCaching/InMemoryStrategy.php |  34 +-
 .../SharedStringsCaching/MemoryLimit.php      |  50 +++
 .../XLSX/Manager/SharedStringsManager.php     | 115 +++---
 .../src/Reader/XLSX/Manager/SheetManager.php  | 163 +++++---
 .../src/Reader/XLSX/Manager/StyleManager.php  | 185 ++++-----
 .../XLSX/Manager/StyleManagerInterface.php    |  31 ++
 .../Manager/WorkbookRelationshipsManager.php  |  59 +--
 lib/openspout/src/Reader/XLSX/Options.php     |  16 +
 lib/openspout/src/Reader/XLSX/Reader.php      | 131 +++---
 lib/openspout/src/Reader/XLSX/RowIterator.php | 178 ++++----
 lib/openspout/src/Reader/XLSX/Sheet.php       |  48 ++-
 .../src/Reader/XLSX/SheetHeaderReader.php     | 119 ++++++
 .../src/Reader/XLSX/SheetIterator.php         |  59 +--
 lib/openspout/src/Writer/AbstractWriter.php   | 175 ++++++++
 .../src/Writer/AbstractWriterMultiSheets.php  | 129 ++++++
 lib/openspout/src/Writer/AutoFilter.php       |  25 ++
 .../src/Writer/CSV/Manager/OptionsManager.php |  34 --
 lib/openspout/src/Writer/CSV/Options.php      |  15 +
 lib/openspout/src/Writer/CSV/Writer.php       |  94 ++---
 .../src/Writer/Common/AbstractOptions.php     |  67 +++
 .../src/Writer/Common/ColumnWidth.php         |  22 +
 .../Common/Creator/InternalEntityFactory.php  |  52 ---
 .../Creator/ManagerFactoryInterface.php       |  23 --
 .../Common/Creator/Style/BorderBuilder.php    |  84 ----
 .../Common/Creator/Style/StyleBuilder.php     | 214 ----------
 .../Common/Creator/WriterEntityFactory.php    | 121 ------
 .../Writer/Common/Creator/WriterFactory.php   |  92 +----
 .../src/Writer/Common/Entity/Options.php      |  30 --
 .../src/Writer/Common/Entity/Sheet.php        | 133 ++++--
 .../src/Writer/Common/Entity/Workbook.php     |  17 +-
 .../src/Writer/Common/Entity/Worksheet.php    |  72 +---
 .../src/Writer/Common/Helper/CellHelper.php   |  12 +-
 ...ileSystemWithRootFolderHelperInterface.php |  14 +-
 .../src/Writer/Common/Helper/ZipHelper.php    | 126 +++---
 ...stract.php => AbstractWorkbookManager.php} | 189 +++------
 .../src/Writer/Common/Manager/CellManager.php |  29 --
 .../Writer/Common/Manager/ManagesCellSize.php |  62 ---
 .../Writer/Common/Manager/RegisteredStyle.php |  16 +-
 .../src/Writer/Common/Manager/RowManager.php  |  25 --
 .../Writer/Common/Manager/SheetManager.php    |  78 ++--
 ...leManager.php => AbstractStyleManager.php} |  22 +-
 ...Registry.php => AbstractStyleRegistry.php} |  45 +-
 .../Manager/Style/PossiblyUpdatedStyle.php    |  11 +-
 .../Manager/Style/StyleManagerInterface.php   |   6 +-
 .../Common/Manager/Style/StyleMerger.php      |  33 +-
 .../Manager/WorkbookManagerInterface.php      |  47 +--
 .../Manager/WorksheetManagerInterface.php     |  33 +-
 .../Exception/Border/InvalidNameException.php |   8 +-
 .../Border/InvalidStyleException.php          |   8 +-
 .../Border/InvalidWidthException.php          |   8 +-
 .../Exception/InvalidSheetNameException.php   |   4 +-
 .../Exception/SheetNotFoundException.php      |   4 +-
 .../WriterAlreadyOpenedException.php          |   4 +-
 .../src/Writer/Exception/WriterException.php  |   6 +-
 .../Exception/WriterNotOpenedException.php    |   4 +-
 .../src/Writer/ODS/Creator/HelperFactory.php  |  54 ---
 .../src/Writer/ODS/Creator/ManagerFactory.php | 107 -----
 .../src/Writer/ODS/Helper/BorderHelper.php    |  23 +-
 .../Writer/ODS/Helper/FileSystemHelper.php    | 138 ++++---
 .../src/Writer/ODS/Manager/OptionsManager.php |  50 ---
 .../Writer/ODS/Manager/Style/StyleManager.php | 284 ++++++-------
 .../ODS/Manager/Style/StyleRegistry.php       |  15 +-
 .../Writer/ODS/Manager/WorkbookManager.php    |  54 +--
 .../Writer/ODS/Manager/WorksheetManager.php   | 167 +++-----
 lib/openspout/src/Writer/ODS/Options.php      |  11 +
 lib/openspout/src/Writer/ODS/Writer.php       |  62 ++-
 lib/openspout/src/Writer/WriterAbstract.php   | 253 ------------
 lib/openspout/src/Writer/WriterInterface.php  |  39 +-
 .../src/Writer/WriterMultiSheetsAbstract.php  | 216 ----------
 .../src/Writer/XLSX/Creator/HelperFactory.php |  53 ---
 .../Writer/XLSX/Creator/ManagerFactory.php    | 145 -------
 .../src/Writer/XLSX/Entity/SheetView.php      | 107 ++---
 .../src/Writer/XLSX/Helper/BorderHelper.php   |  26 +-
 .../src/Writer/XLSX/Helper/DateHelper.php     |  29 +-
 .../Writer/XLSX/Helper/FileSystemHelper.php   | 385 ++++++++++++++----
 .../Writer/XLSX/Manager/CommentsManager.php   | 225 ++++++++++
 .../Writer/XLSX/Manager/OptionsManager.php    |  64 ---
 .../XLSX/Manager/SharedStringsManager.php     |  45 +-
 .../XLSX/Manager/Style/StyleManager.php       | 105 ++---
 .../XLSX/Manager/Style/StyleRegistry.php      | 104 ++---
 .../Writer/XLSX/Manager/WorkbookManager.php   |  60 +--
 .../Writer/XLSX/Manager/WorksheetManager.php  | 218 +++-------
 lib/openspout/src/Writer/XLSX/MergeCell.php   |  27 ++
 lib/openspout/src/Writer/XLSX/Options.php     |  66 +++
 lib/openspout/src/Writer/XLSX/Writer.php      | 112 ++---
 lib/thirdpartylibs.xml                        |   2 +-
 180 files changed, 4575 insertions(+), 7416 deletions(-)
 delete mode 100644 lib/openspout/src/Autoloader/Psr4Autoloader.php
 delete mode 100644 lib/openspout/src/Autoloader/autoload.php
 delete mode 100644 lib/openspout/src/Common/Creator/HelperFactory.php
 create mode 100644 lib/openspout/src/Common/Entity/Cell/BooleanCell.php
 create mode 100644 lib/openspout/src/Common/Entity/Cell/DateIntervalCell.php
 create mode 100644 lib/openspout/src/Common/Entity/Cell/DateTimeCell.php
 create mode 100644 lib/openspout/src/Common/Entity/Cell/EmptyCell.php
 create mode 100644 lib/openspout/src/Common/Entity/Cell/ErrorCell.php
 create mode 100644 lib/openspout/src/Common/Entity/Cell/FormulaCell.php
 create mode 100644 lib/openspout/src/Common/Entity/Cell/NumericCell.php
 create mode 100644 lib/openspout/src/Common/Entity/Cell/StringCell.php
 create mode 100644 lib/openspout/src/Common/Entity/Comment/Comment.php
 create mode 100644 lib/openspout/src/Common/Entity/Comment/TextRun.php
 create mode 100644 lib/openspout/src/Common/Entity/Style/CellVerticalAlignment.php
 create mode 100644 lib/openspout/src/Common/Exception/OpenSpoutException.php
 delete mode 100644 lib/openspout/src/Common/Exception/SpoutException.php
 delete mode 100644 lib/openspout/src/Common/Helper/CellTypeHelper.php
 delete mode 100644 lib/openspout/src/Common/Helper/Escaper/CSV.php
 delete mode 100644 lib/openspout/src/Common/Helper/GlobalFunctionsHelper.php
 delete mode 100644 lib/openspout/src/Common/Manager/OptionsManagerAbstract.php
 delete mode 100644 lib/openspout/src/Common/Manager/OptionsManagerInterface.php
 create mode 100644 lib/openspout/src/Common/TempFolderOptionTrait.php
 delete mode 100644 lib/openspout/src/Common/Type.php
 rename lib/openspout/src/Reader/{ReaderAbstract.php => AbstractReader.php} (52%)
 delete mode 100644 lib/openspout/src/Reader/CSV/Creator/InternalEntityFactory.php
 delete mode 100644 lib/openspout/src/Reader/CSV/Manager/OptionsManager.php
 create mode 100644 lib/openspout/src/Reader/CSV/Options.php
 create mode 100644 lib/openspout/src/Reader/Common/ColumnWidth.php
 delete mode 100644 lib/openspout/src/Reader/Common/Creator/InternalEntityFactoryInterface.php
 delete mode 100644 lib/openspout/src/Reader/Common/Creator/ReaderEntityFactory.php
 delete mode 100644 lib/openspout/src/Reader/Common/Entity/Options.php
 delete mode 100644 lib/openspout/src/Reader/IteratorInterface.php
 delete mode 100644 lib/openspout/src/Reader/ODS/Creator/HelperFactory.php
 delete mode 100644 lib/openspout/src/Reader/ODS/Creator/InternalEntityFactory.php
 delete mode 100644 lib/openspout/src/Reader/ODS/Creator/ManagerFactory.php
 delete mode 100644 lib/openspout/src/Reader/ODS/Manager/OptionsManager.php
 create mode 100644 lib/openspout/src/Reader/ODS/Options.php
 create mode 100644 lib/openspout/src/Reader/SheetWithVisibilityInterface.php
 delete mode 100644 lib/openspout/src/Reader/XLSX/Creator/HelperFactory.php
 delete mode 100644 lib/openspout/src/Reader/XLSX/Creator/InternalEntityFactory.php
 delete mode 100644 lib/openspout/src/Reader/XLSX/Creator/ManagerFactory.php
 delete mode 100644 lib/openspout/src/Reader/XLSX/Manager/OptionsManager.php
 create mode 100644 lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/MemoryLimit.php
 create mode 100644 lib/openspout/src/Reader/XLSX/Manager/StyleManagerInterface.php
 create mode 100644 lib/openspout/src/Reader/XLSX/Options.php
 create mode 100644 lib/openspout/src/Reader/XLSX/SheetHeaderReader.php
 create mode 100644 lib/openspout/src/Writer/AbstractWriter.php
 create mode 100644 lib/openspout/src/Writer/AbstractWriterMultiSheets.php
 create mode 100644 lib/openspout/src/Writer/AutoFilter.php
 delete mode 100644 lib/openspout/src/Writer/CSV/Manager/OptionsManager.php
 create mode 100644 lib/openspout/src/Writer/CSV/Options.php
 create mode 100644 lib/openspout/src/Writer/Common/AbstractOptions.php
 create mode 100644 lib/openspout/src/Writer/Common/ColumnWidth.php
 delete mode 100644 lib/openspout/src/Writer/Common/Creator/InternalEntityFactory.php
 delete mode 100644 lib/openspout/src/Writer/Common/Creator/ManagerFactoryInterface.php
 delete mode 100644 lib/openspout/src/Writer/Common/Creator/Style/BorderBuilder.php
 delete mode 100644 lib/openspout/src/Writer/Common/Creator/Style/StyleBuilder.php
 delete mode 100644 lib/openspout/src/Writer/Common/Creator/WriterEntityFactory.php
 delete mode 100644 lib/openspout/src/Writer/Common/Entity/Options.php
 rename lib/openspout/src/Writer/Common/Manager/{WorkbookManagerAbstract.php => AbstractWorkbookManager.php} (60%)
 delete mode 100644 lib/openspout/src/Writer/Common/Manager/CellManager.php
 delete mode 100644 lib/openspout/src/Writer/Common/Manager/ManagesCellSize.php
 delete mode 100644 lib/openspout/src/Writer/Common/Manager/RowManager.php
 rename lib/openspout/src/Writer/Common/Manager/Style/{StyleManager.php => AbstractStyleManager.php} (73%)
 rename lib/openspout/src/Writer/Common/Manager/Style/{StyleRegistry.php => AbstractStyleRegistry.php} (66%)
 delete mode 100644 lib/openspout/src/Writer/ODS/Creator/HelperFactory.php
 delete mode 100644 lib/openspout/src/Writer/ODS/Creator/ManagerFactory.php
 delete mode 100644 lib/openspout/src/Writer/ODS/Manager/OptionsManager.php
 create mode 100644 lib/openspout/src/Writer/ODS/Options.php
 delete mode 100644 lib/openspout/src/Writer/WriterAbstract.php
 delete mode 100644 lib/openspout/src/Writer/WriterMultiSheetsAbstract.php
 delete mode 100644 lib/openspout/src/Writer/XLSX/Creator/HelperFactory.php
 delete mode 100644 lib/openspout/src/Writer/XLSX/Creator/ManagerFactory.php
 create mode 100644 lib/openspout/src/Writer/XLSX/Manager/CommentsManager.php
 delete mode 100644 lib/openspout/src/Writer/XLSX/Manager/OptionsManager.php
 create mode 100644 lib/openspout/src/Writer/XLSX/MergeCell.php
 create mode 100644 lib/openspout/src/Writer/XLSX/Options.php

diff --git a/lib/openspout/README.md b/lib/openspout/README.md
index 0ceb637f69e..d7499fc08da 100644
--- a/lib/openspout/README.md
+++ b/lib/openspout/README.md
@@ -1,43 +1,27 @@
 # OpenSpout
 
 [![Latest Stable Version](https://poser.pugx.org/openspout/openspout/v/stable)](https://packagist.org/packages/openspout/openspout)
-[![Build Status](https://github.com/openspout/openspout/actions/workflows/ci.yml/badge.svg)](https://github.com/openspout/openspout/actions/workflows/ci.yml)
-[![Code Coverage](https://codecov.io/gh/openspout/openspout/coverage.svg?branch=main)](https://codecov.io/gh/openspout/openspout?branch=main)
 [![Total Downloads](https://poser.pugx.org/openspout/openspout/downloads)](https://packagist.org/packages/openspout/openspout)
+[![Build Status](https://github.com/openspout/openspout/actions/workflows/ci.yml/badge.svg)](https://github.com/openspout/openspout/actions/workflows/ci.yml)
+[![Infection MSI](https://badge.stryker-mutator.io/github.com/openspout/openspout/4.x)](https://dashboard.stryker-mutator.io/reports/github.com/openspout/openspout/4.x)
 
-OpenSpout is a community driven fork of `box/spout`, a PHP library to read and write spreadsheet files (CSV, XLSX and ODS), in a fast and scalable way.
-Unlike other file readers or writers, it is capable of processing very large files, while keeping the memory usage really low (less than 3MB).
+OpenSpout is a community driven fork of `box/spout`, a PHP library to read and write spreadsheet files
+(CSV, XLSX and ODS), in a fast and scalable way. Unlike other file readers or writers, it is capable of processing
+very large files, while keeping the memory usage really low (less than 3MB).
 
 ## Documentation
 
-Documentation can be found at [https://openspout.readthedocs.io/en/latest/](https://openspout.readthedocs.io/en/latest/).
+Documentation can be found at [`docs/`](docs).
 
-## Requirements
-
-* PHP version 7.3 or higher
-* PHP extension `php_zip` enabled
-* PHP extension `php_xmlreader` enabled
-
-## Upgrade from `box/spout`
+## Upgrade from `box/spout:v3` to `openspout/openspout:v3`
 
 1. Replace `box/spout` with `openspout/openspout` in your `composer.json`
 2. Replace `Box\Spout` with `OpenSpout` in your code
 
 ## Upgrade guide
 
-Version 3 introduced new functionality but also some breaking changes. If you want to upgrade your Spout codebase from version 2 please consult the [Upgrade guide](UPGRADE-3.0.md). 
-
-## Running tests
-
-The `main` branch includes unit, functional and performance tests.
-If you just want to check that everything is working as expected, executing the unit and functional tests is enough.
-
-* `phpunit` - runs unit and functional tests
-* `phpunit --group perf-tests` - only runs the performance tests
-
-For information, the performance tests take about 10 minutes to run (processing 1 million rows files is not a quick thing).
-
-> Performance tests status: [![Build Status](https://travis-ci.org/box/spout.svg?branch=perf-tests)](https://travis-ci.org/box/spout)
+Version 4 introduced new functionality but also some breaking changes. If you want to upgrade your OpenSpout codebase
+please consult the [Upgrade guide](UPGRADE.md).
 
 ## Copyright and License
 
diff --git a/lib/openspout/src/Autoloader/Psr4Autoloader.php b/lib/openspout/src/Autoloader/Psr4Autoloader.php
deleted file mode 100644
index 59eac315696..00000000000
--- a/lib/openspout/src/Autoloader/Psr4Autoloader.php
+++ /dev/null
@@ -1,147 +0,0 @@
-<?php
-
-namespace OpenSpout\Autoloader;
-
-/**
- * @see https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-4-autoloader-examples.md#class-example
- */
-class Psr4Autoloader
-{
-    /**
-     * An associative array where the key is a namespace prefix and the value
-     * is an array of base directories for classes in that namespace.
-     *
-     * @var array
-     */
-    protected $prefixes = [];
-
-    /**
-     * Register loader with SPL autoloader stack.
-     */
-    public function register()
-    {
-        spl_autoload_register([$this, 'loadClass']);
-    }
-
-    /**
-     * Adds a base directory for a namespace prefix.
-     *
-     * @param string $prefix  the namespace prefix
-     * @param string $baseDir a base directory for class files in the
-     *                        namespace
-     * @param bool   $prepend if true, prepend the base directory to the stack
-     *                        instead of appending it; this causes it to be searched first rather
-     *                        than last
-     */
-    public function addNamespace($prefix, $baseDir, $prepend = false)
-    {
-        // normalize namespace prefix
-        $prefix = trim($prefix, '\\').'\\';
-
-        // normalize the base directory with a trailing separator
-        $baseDir = rtrim($baseDir, \DIRECTORY_SEPARATOR).'/';
-
-        // initialize the namespace prefix array
-        if (false === isset($this->prefixes[$prefix])) {
-            $this->prefixes[$prefix] = [];
-        }
-
-        // retain the base directory for the namespace prefix
-        if ($prepend) {
-            array_unshift($this->prefixes[$prefix], $baseDir);
-        } else {
-            $this->prefixes[$prefix][] = $baseDir;
-        }
-    }
-
-    /**
-     * Loads the class file for a given class name.
-     *
-     * @param string $class the fully-qualified class name
-     *
-     * @return mixed the mapped file name on success, or boolean false on
-     *               failure
-     */
-    public function loadClass($class)
-    {
-        // the current namespace prefix
-        $prefix = $class;
-
-        // work backwards through the namespace names of the fully-qualified
-        // class name to find a mapped file name
-        while (($pos = strrpos($prefix, '\\')) !== false) {
-            // retain the trailing namespace separator in the prefix
-            $prefix = substr($class, 0, $pos + 1);
-
-            // the rest is the relative class name
-            $relativeClass = substr($class, $pos + 1);
-
-            // try to load a mapped file for the prefix and relative class
-            $mappedFile = $this->loadMappedFile($prefix, $relativeClass);
-            if (false !== $mappedFile) {
-                return $mappedFile;
-            }
-
-            // remove the trailing namespace separator for the next iteration
-            // of strrpos()
-            $prefix = rtrim($prefix, '\\');
-        }
-
-        // never found a mapped file
-        return false;
-    }
-
-    /**
-     * Load the mapped file for a namespace prefix and relative class.
-     *
-     * @param string $prefix        the namespace prefix
-     * @param string $relativeClass the relative class name
-     *
-     * @return mixed boolean false if no mapped file can be loaded, or the
-     *               name of the mapped file that was loaded
-     */
-    protected function loadMappedFile($prefix, $relativeClass)
-    {
-        // are there any base directories for this namespace prefix?
-        if (false === isset($this->prefixes[$prefix])) {
-            return false;
-        }
-
-        // look through base directories for this namespace prefix
-        foreach ($this->prefixes[$prefix] as $baseDir) {
-            // replace the namespace prefix with the base directory,
-            // replace namespace separators with directory separators
-            // in the relative class name, append with .php
-            $file = $baseDir
-                  .str_replace('\\', '/', $relativeClass)
-                  .'.php';
-
-            // if the mapped file exists, require it
-            if ($this->requireFile($file)) {
-                // yes, we're done
-                return $file;
-            }
-        }
-
-        // never found it
-        return false;
-    }
-
-    /**
-     * If a file exists, require it from the file system.
-     *
-     * @param string $file the file to require
-     *
-     * @return bool true if the file exists, false if not
-     */
-    protected function requireFile($file)
-    {
-        if (file_exists($file)) {
-            require $file;
-
-            return true;
-        }
-
-        return false;
-    }
-}
diff --git a/lib/openspout/src/Autoloader/autoload.php b/lib/openspout/src/Autoloader/autoload.php
deleted file mode 100644
index a6768d4e849..00000000000
--- a/lib/openspout/src/Autoloader/autoload.php
+++ /dev/null
@@ -1,15 +0,0 @@
-<?php
-
-namespace OpenSpout\Autoloader;
-
-require_once 'Psr4Autoloader.php';
-
-/**
- * @var string
- *             Full path to "src/Spout" which is what we want "OpenSpout" to map to
- */
-$srcBaseDirectory = \dirname(__DIR__);
-
-$loader = new Psr4Autoloader();
-$loader->register();
-$loader->addNamespace('OpenSpout', $srcBaseDirectory);
diff --git a/lib/openspout/src/Common/Creator/HelperFactory.php b/lib/openspout/src/Common/Creator/HelperFactory.php
deleted file mode 100644
index 55f1f57bf7e..00000000000
--- a/lib/openspout/src/Common/Creator/HelperFactory.php
+++ /dev/null
@@ -1,48 +0,0 @@
-<?php
-
-namespace OpenSpout\Common\Creator;
-
-use OpenSpout\Common\Helper\EncodingHelper;
-use OpenSpout\Common\Helper\FileSystemHelper;
-use OpenSpout\Common\Helper\GlobalFunctionsHelper;
-use OpenSpout\Common\Helper\StringHelper;
-
-/**
- * Factory to create helpers.
- */
-class HelperFactory
-{
-    /**
-     * @return GlobalFunctionsHelper
-     */
-    public function createGlobalFunctionsHelper()
-    {
-        return new GlobalFunctionsHelper();
-    }
-
-    /**
-     * @param string $baseFolderPath The path of the base folder where all the I/O can occur
-     *
-     * @return FileSystemHelper
-     */
-    public function createFileSystemHelper($baseFolderPath)
-    {
-        return new FileSystemHelper($baseFolderPath);
-    }
-
-    /**
-     * @return EncodingHelper
-     */
-    public function createEncodingHelper(GlobalFunctionsHelper $globalFunctionsHelper)
-    {
-        return new EncodingHelper($globalFunctionsHelper);
-    }
-
-    /**
-     * @return StringHelper
-     */
-    public function createStringHelper()
-    {
-        return new StringHelper();
-    }
-}
diff --git a/lib/openspout/src/Common/Entity/Cell.php b/lib/openspout/src/Common/Entity/Cell.php
index a9d4dfee207..2cd263f2f02 100644
--- a/lib/openspout/src/Common/Entity/Cell.php
+++ b/lib/openspout/src/Common/Entity/Cell.php
@@ -1,227 +1,65 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Entity;
 
+use DateInterval;
+use DateTimeInterface;
+use OpenSpout\Common\Entity\Cell\BooleanCell;
+use OpenSpout\Common\Entity\Cell\DateIntervalCell;
+use OpenSpout\Common\Entity\Cell\DateTimeCell;
+use OpenSpout\Common\Entity\Cell\EmptyCell;
+use OpenSpout\Common\Entity\Cell\FormulaCell;
+use OpenSpout\Common\Entity\Cell\NumericCell;
+use OpenSpout\Common\Entity\Cell\StringCell;
+use OpenSpout\Common\Entity\Comment\Comment;
 use OpenSpout\Common\Entity\Style\Style;
-use OpenSpout\Common\Helper\CellTypeHelper;
 
-class Cell
+abstract class Cell
 {
-    /**
-     * Numeric cell type (whole numbers, fractional numbers, dates).
-     */
-    public const TYPE_NUMERIC = 0;
+    public ?Comment $comment = null;
 
-    /**
-     * String (text) cell type.
-     */
-    public const TYPE_STRING = 1;
+    private Style $style;
 
-    /**
-     * Formula cell type
-     * Not used at the moment.
-     */
-    public const TYPE_FORMULA = 2;
-
-    /**
-     * Empty cell type.
-     */
-    public const TYPE_EMPTY = 3;
-
-    /**
-     * Boolean cell type.
-     */
-    public const TYPE_BOOLEAN = 4;
-
-    /**
-     * Date cell type.
-     */
-    public const TYPE_DATE = 5;
-
-    /**
-     * Error cell type.
-     */
-    public const TYPE_ERROR = 6;
-
-    /**
-     * The value of this cell.
-     *
-     * @var null|mixed
-     */
-    protected $value;
-
-    /**
-     * The cell type.
-     *
-     * @var null|int
-     */
-    protected $type;
-
-    /**
-     * The cell style.
-     *
-     * @var Style
-     */
-    protected $style;
-
-    /**
-     * @param null|mixed $value
-     */
-    public function __construct($value, Style $style = null)
+    public function __construct(?Style $style)
     {
-        $this->setValue($value);
         $this->setStyle($style);
     }
 
-    /**
-     * @return string
-     */
-    public function __toString()
+    abstract public function getValue(): null|bool|string|int|float|DateTimeInterface|DateInterval;
+
+    final public function setStyle(?Style $style): void
     {
-        return (string) $this->getValue();
+        $this->style = $style ?? new Style();
     }
 
-    /**
-     * @param null|mixed $value
-     */
-    public function setValue($value)
-    {
-        $this->value = $value;
-        $this->type = $this->detectType($value);
-    }
-
-    /**
-     * @return null|mixed
-     */
-    public function getValue()
-    {
-        return !$this->isError() ? $this->value : null;
-    }
-
-    /**
-     * @return mixed
-     */
-    public function getValueEvenIfError()
-    {
-        return $this->value;
-    }
-
-    /**
-     * @param null|Style $style
-     */
-    public function setStyle($style)
-    {
-        $this->style = $style ?: new Style();
-    }
-
-    /**
-     * @return Style
-     */
-    public function getStyle()
+    final public function getStyle(): Style
     {
         return $this->style;
     }
 
-    /**
-     * @return null|int
-     */
-    public function getType()
+    final public static function fromValue(null|bool|string|int|float|DateTimeInterface|DateInterval $value, ?Style $style = null): self
     {
-        return $this->type;
-    }
-
-    /**
-     * @param int $type
-     */
-    public function setType($type)
-    {
-        $this->type = $type;
-    }
-
-    /**
-     * @return bool
-     */
-    public function isBoolean()
-    {
-        return self::TYPE_BOOLEAN === $this->type;
-    }
-
-    /**
-     * @return bool
-     */
-    public function isEmpty()
-    {
-        return self::TYPE_EMPTY === $this->type;
-    }
-
-    /**
-     * @return bool
-     */
-    public function isNumeric()
-    {
-        return self::TYPE_NUMERIC === $this->type;
-    }
-
-    /**
-     * @return bool
-     */
-    public function isString()
-    {
-        return self::TYPE_STRING === $this->type;
-    }
-
-    /**
-     * @return bool
-     */
-    public function isDate()
-    {
-        return self::TYPE_DATE === $this->type;
-    }
-
-    /**
-     * @return bool
-     */
-    public function isFormula()
-    {
-        return self::TYPE_FORMULA === $this->type;
-    }
-
-    /**
-     * @return bool
-     */
-    public function isError()
-    {
-        return self::TYPE_ERROR === $this->type;
-    }
-
-    /**
-     * Get the current value type.
-     *
-     * @param null|mixed $value
-     *
-     * @return int
-     */
-    protected function detectType($value)
-    {
-        if (CellTypeHelper::isBoolean($value)) {
-            return self::TYPE_BOOLEAN;
+        if (\is_bool($value)) {
+            return new BooleanCell($value, $style);
         }
-        if (CellTypeHelper::isEmpty($value)) {
-            return self::TYPE_EMPTY;
+        if (null === $value || '' === $value) {
+            return new EmptyCell($value, $style);
         }
-        if (CellTypeHelper::isNumeric($value)) {
-            return self::TYPE_NUMERIC;
+        if (\is_int($value) || \is_float($value)) {
+            return new NumericCell($value, $style);
         }
-        if (CellTypeHelper::isDateTimeOrDateInterval($value)) {
-            return self::TYPE_DATE;
+        if ($value instanceof DateTimeInterface) {
+            return new DateTimeCell($value, $style);
         }
-        if (CellTypeHelper::isFormula($value)) {
-            return self::TYPE_FORMULA;
+        if ($value instanceof DateInterval) {
+            return new DateIntervalCell($value, $style);
         }
-        if (CellTypeHelper::isNonEmptyString($value)) {
-            return self::TYPE_STRING;
+        if (isset($value[0]) && '=' === $value[0]) {
+            return new FormulaCell($value, $style);
         }
 
-        return self::TYPE_ERROR;
+        return new StringCell($value, $style);
     }
 }
diff --git a/lib/openspout/src/Common/Entity/Cell/BooleanCell.php b/lib/openspout/src/Common/Entity/Cell/BooleanCell.php
new file mode 100644
index 00000000000..120a72b8a00
--- /dev/null
+++ b/lib/openspout/src/Common/Entity/Cell/BooleanCell.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Entity\Cell;
+
+use OpenSpout\Common\Entity\Cell;
+use OpenSpout\Common\Entity\Style\Style;
+
+final class BooleanCell extends Cell
+{
+    private bool $value;
+
+    public function __construct(bool $value, ?Style $style)
+    {
+        $this->value = $value;
+        parent::__construct($style);
+    }
+
+    public function getValue(): bool
+    {
+        return $this->value;
+    }
+}
diff --git a/lib/openspout/src/Common/Entity/Cell/DateIntervalCell.php b/lib/openspout/src/Common/Entity/Cell/DateIntervalCell.php
new file mode 100644
index 00000000000..75b5eaf5916
--- /dev/null
+++ b/lib/openspout/src/Common/Entity/Cell/DateIntervalCell.php
@@ -0,0 +1,25 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Entity\Cell;
+
+use DateInterval;
+use OpenSpout\Common\Entity\Cell;
+use OpenSpout\Common\Entity\Style\Style;
+
+final class DateIntervalCell extends Cell
+{
+    private DateInterval $value;
+
+    public function __construct(DateInterval $value, ?Style $style)
+    {
+        $this->value = $value;
+        parent::__construct($style);
+    }
+
+    public function getValue(): DateInterval
+    {
+        return $this->value;
+    }
+}
diff --git a/lib/openspout/src/Common/Entity/Cell/DateTimeCell.php b/lib/openspout/src/Common/Entity/Cell/DateTimeCell.php
new file mode 100644
index 00000000000..7065abf5445
--- /dev/null
+++ b/lib/openspout/src/Common/Entity/Cell/DateTimeCell.php
@@ -0,0 +1,25 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Entity\Cell;
+
+use DateTimeInterface;
+use OpenSpout\Common\Entity\Cell;
+use OpenSpout\Common\Entity\Style\Style;
+
+final class DateTimeCell extends Cell
+{
+    private DateTimeInterface $value;
+
+    public function __construct(DateTimeInterface $value, ?Style $style)
+    {
+        $this->value = $value;
+        parent::__construct($style);
+    }
+
+    public function getValue(): DateTimeInterface
+    {
+        return $this->value;
+    }
+}
diff --git a/lib/openspout/src/Common/Entity/Cell/EmptyCell.php b/lib/openspout/src/Common/Entity/Cell/EmptyCell.php
new file mode 100644
index 00000000000..8d3e41399c4
--- /dev/null
+++ b/lib/openspout/src/Common/Entity/Cell/EmptyCell.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Entity\Cell;
+
+use OpenSpout\Common\Entity\Cell;
+use OpenSpout\Common\Entity\Style\Style;
+
+final class EmptyCell extends Cell
+{
+    private ?string $value;
+
+    public function __construct(?string $value, ?Style $style)
+    {
+        $this->value = $value;
+        parent::__construct($style);
+    }
+
+    public function getValue(): ?string
+    {
+        return $this->value;
+    }
+}
diff --git a/lib/openspout/src/Common/Entity/Cell/ErrorCell.php b/lib/openspout/src/Common/Entity/Cell/ErrorCell.php
new file mode 100644
index 00000000000..2c1d677bd99
--- /dev/null
+++ b/lib/openspout/src/Common/Entity/Cell/ErrorCell.php
@@ -0,0 +1,29 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Entity\Cell;
+
+use OpenSpout\Common\Entity\Cell;
+use OpenSpout\Common\Entity\Style\Style;
+
+final class ErrorCell extends Cell
+{
+    private string $value;
+
+    public function __construct(string $value, ?Style $style)
+    {
+        $this->value = $value;
+        parent::__construct($style);
+    }
+
+    public function getValue(): ?string
+    {
+        return null;
+    }
+
+    public function getRawValue(): string
+    {
+        return $this->value;
+    }
+}
diff --git a/lib/openspout/src/Common/Entity/Cell/FormulaCell.php b/lib/openspout/src/Common/Entity/Cell/FormulaCell.php
new file mode 100644
index 00000000000..97daa838cb6
--- /dev/null
+++ b/lib/openspout/src/Common/Entity/Cell/FormulaCell.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Entity\Cell;
+
+use OpenSpout\Common\Entity\Cell;
+use OpenSpout\Common\Entity\Style\Style;
+
+final class FormulaCell extends Cell
+{
+    private string $value;
+
+    public function __construct(string $value, ?Style $style)
+    {
+        $this->value = $value;
+        parent::__construct($style);
+    }
+
+    public function getValue(): string
+    {
+        return $this->value;
+    }
+}
diff --git a/lib/openspout/src/Common/Entity/Cell/NumericCell.php b/lib/openspout/src/Common/Entity/Cell/NumericCell.php
new file mode 100644
index 00000000000..810fe1113d5
--- /dev/null
+++ b/lib/openspout/src/Common/Entity/Cell/NumericCell.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Entity\Cell;
+
+use OpenSpout\Common\Entity\Cell;
+use OpenSpout\Common\Entity\Style\Style;
+
+final class NumericCell extends Cell
+{
+    private int|float $value;
+
+    public function __construct(int|float $value, ?Style $style)
+    {
+        $this->value = $value;
+        parent::__construct($style);
+    }
+
+    public function getValue(): int|float
+    {
+        return $this->value;
+    }
+}
diff --git a/lib/openspout/src/Common/Entity/Cell/StringCell.php b/lib/openspout/src/Common/Entity/Cell/StringCell.php
new file mode 100644
index 00000000000..94ffa8fa6d2
--- /dev/null
+++ b/lib/openspout/src/Common/Entity/Cell/StringCell.php
@@ -0,0 +1,24 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Entity\Cell;
+
+use OpenSpout\Common\Entity\Cell;
+use OpenSpout\Common\Entity\Style\Style;
+
+final class StringCell extends Cell
+{
+    private string $value;
+
+    public function __construct(string $value, ?Style $style)
+    {
+        $this->value = $value;
+        parent::__construct($style);
+    }
+
+    public function getValue(): string
+    {
+        return $this->value;
+    }
+}
diff --git a/lib/openspout/src/Common/Entity/Comment/Comment.php b/lib/openspout/src/Common/Entity/Comment/Comment.php
new file mode 100644
index 00000000000..47753df4e96
--- /dev/null
+++ b/lib/openspout/src/Common/Entity/Comment/Comment.php
@@ -0,0 +1,47 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Entity\Comment;
+
+/**
+ * This class defines a comment that can be added to a cell.
+ */
+final class Comment
+{
+    /** Comment height (CSS style, i.e. XXpx or YYpt). */
+    public string $height = '55.5pt';
+
+    /** Comment width (CSS style, i.e. XXpx or YYpt). */
+    public string $width = '96pt';
+
+    /** Left margin (CSS style, i.e. XXpx or YYpt). */
+    public string $marginLeft = '59.25pt';
+
+    /** Top margin (CSS style, i.e. XXpx or YYpt). */
+    public string $marginTop = '1.5pt';
+
+    /** Visible. */
+    public bool $visible = false;
+
+    /** Comment fill color. */
+    public string $fillColor = '#FFFFE1';
+
+    /** @var TextRun[] */
+    private array $textRuns = [];
+
+    public function addTextRun(?TextRun $textRun): void
+    {
+        $this->textRuns[] = $textRun;
+    }
+
+    /**
+     * The TextRuns for this comment.
+     *
+     * @return TextRun[]
+     */
+    public function getTextRuns(): array
+    {
+        return $this->textRuns;
+    }
+}
diff --git a/lib/openspout/src/Common/Entity/Comment/TextRun.php b/lib/openspout/src/Common/Entity/Comment/TextRun.php
new file mode 100644
index 00000000000..16bc23eb5da
--- /dev/null
+++ b/lib/openspout/src/Common/Entity/Comment/TextRun.php
@@ -0,0 +1,23 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Entity\Comment;
+
+/**
+ * This class defines rich text in a fluent interface that can be added to a comment.
+ */
+final class TextRun
+{
+    public string $text;
+    public int $fontSize = 10;
+    public string $fontColor = '000000';
+    public string $fontName = 'Tahoma';
+    public bool $bold = false;
+    public bool $italic = false;
+
+    public function __construct(string $text)
+    {
+        $this->text = $text;
+    }
+}
diff --git a/lib/openspout/src/Common/Entity/Row.php b/lib/openspout/src/Common/Entity/Row.php
index db6481fc4df..6443ea19bf7 100644
--- a/lib/openspout/src/Common/Entity/Row.php
+++ b/lib/openspout/src/Common/Entity/Row.php
@@ -1,39 +1,34 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Entity;
 
+use DateInterval;
+use DateTimeInterface;
 use OpenSpout\Common\Entity\Style\Style;
 
-class Row
+final class Row
 {
     /**
      * The cells in this row.
      *
      * @var Cell[]
      */
-    protected $cells = [];
+    private array $cells = [];
 
-    /**
-     * The row style.
-     *
-     * @var Style
-     */
-    protected $style;
+    /** The row style. */
+    private Style $style;
 
-    /**
-     * Row height (default is 15).
-     *
-     * @var string
-     */
-    protected $height = '15';
+    /** Row height. */
+    private float $height = 0;
 
     /**
      * Row constructor.
      *
-     * @param Cell[]     $cells
-     * @param null|Style $style
+     * @param Cell[] $cells
      */
-    public function __construct(array $cells, $style)
+    public function __construct(array $cells, ?Style $style = null)
     {
         $this
             ->setCells($cells)
@@ -41,20 +36,30 @@ class Row
         ;
     }
 
+    /**
+     * @param list<null|bool|DateInterval|DateTimeInterface|float|int|string> $cellValues
+     */
+    public static function fromValues(array $cellValues = [], ?Style $rowStyle = null): self
+    {
+        $cells = array_map(static function (null|bool|string|int|float|DateTimeInterface|DateInterval $cellValue): Cell {
+            return Cell::fromValue($cellValue);
+        }, $cellValues);
+
+        return new self($cells, $rowStyle);
+    }
+
     /**
      * @return Cell[] $cells
      */
-    public function getCells()
+    public function getCells(): array
     {
         return $this->cells;
     }
 
     /**
      * @param Cell[] $cells
-     *
-     * @return Row
      */
-    public function setCells(array $cells)
+    public function setCells(array $cells): self
     {
         $this->cells = [];
         foreach ($cells as $cell) {
@@ -64,90 +69,52 @@ class Row
         return $this;
     }
 
-    /**
-     * @param int $cellIndex
-     *
-     * @return Row
-     */
-    public function setCellAtIndex(Cell $cell, $cellIndex)
+    public function setCellAtIndex(Cell $cell, int $cellIndex): self
     {
         $this->cells[$cellIndex] = $cell;
 
         return $this;
     }
 
-    /**
-     * @param int $cellIndex
-     *
-     * @return null|Cell
-     */
-    public function getCellAtIndex($cellIndex)
+    public function getCellAtIndex(int $cellIndex): ?Cell
     {
         return $this->cells[$cellIndex] ?? null;
     }
 
-    /**
-     * @return Row
-     */
-    public function addCell(Cell $cell)
+    public function addCell(Cell $cell): self
     {
         $this->cells[] = $cell;
 
         return $this;
     }
 
-    /**
-     * @return int
-     */
-    public function getNumCells()
+    public function getNumCells(): int
     {
         // When using "setCellAtIndex", it's possible to
         // have "$this->cells" contain holes.
-        if (empty($this->cells)) {
+        if ([] === $this->cells) {
             return 0;
         }
 
         return max(array_keys($this->cells)) + 1;
     }
 
-    /**
-     * @return Style
-     */
-    public function getStyle()
+    public function getStyle(): Style
     {
         return $this->style;
     }
 
-    /**
-     * @param null|Style $style
-     *
-     * @return Row
-     */
-    public function setStyle($style)
+    public function setStyle(?Style $style): self
     {
-        $this->style = $style ?: new Style();
+        $this->style = $style ?? new Style();
 
         return $this;
     }
 
-    /**
-     * @return array The row values, as array
-     */
-    public function toArray()
-    {
-        return array_map(function (Cell $cell) {
-            return $cell->getValue();
-        }, $this->cells);
-    }
-
     /**
      * Set row height.
-     *
-     * @param string $height
-     *
-     * @return Row
      */
-    public function setHeight($height)
+    public function setHeight(float $height): self
     {
         $this->height = $height;
 
@@ -156,11 +123,34 @@ class Row
 
     /**
      * Returns row height.
-     *
-     * @return string
      */
-    public function getHeight()
+    public function getHeight(): float
     {
         return $this->height;
     }
+
+    /**
+     * @return list<null|bool|DateInterval|DateTimeInterface|float|int|string> The row values, as array
+     */
+    public function toArray(): array
+    {
+        return array_map(static function (Cell $cell): null|bool|string|int|float|DateTimeInterface|DateInterval {
+            return $cell->getValue();
+        }, $this->cells);
+    }
+
+    /**
+     * Detect whether a row is considered empty.
+     * An empty row has all of its cells empty.
+     */
+    public function isEmpty(): bool
+    {
+        foreach ($this->cells as $cell) {
+            if (!$cell instanceof Cell\EmptyCell) {
+                return false;
+            }
+        }
+
+        return true;
+    }
 }
diff --git a/lib/openspout/src/Common/Entity/Style/Border.php b/lib/openspout/src/Common/Entity/Style/Border.php
index 53b59dab756..487edaa3234 100644
--- a/lib/openspout/src/Common/Entity/Style/Border.php
+++ b/lib/openspout/src/Common/Entity/Style/Border.php
@@ -1,8 +1,10 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Entity\Style;
 
-class Border
+final class Border
 {
     public const LEFT = 'left';
     public const RIGHT = 'right';
@@ -19,62 +21,26 @@ class Border
     public const WIDTH_MEDIUM = 'medium';
     public const WIDTH_THICK = 'thick';
 
-    /** @var array A list of BorderPart objects for this border. */
-    private $parts = [];
+    /** @var array<string, BorderPart> */
+    private array $parts;
 
-    public function __construct(array $borderParts = [])
+    public function __construct(BorderPart ...$borderParts)
     {
-        $this->setParts($borderParts);
-    }
-
-    /**
-     * @param string $name The name of the border part
-     *
-     * @return null|BorderPart
-     */
-    public function getPart($name)
-    {
-        return $this->hasPart($name) ? $this->parts[$name] : null;
-    }
-
-    /**
-     * @param string $name The name of the border part
-     *
-     * @return bool
-     */
-    public function hasPart($name)
-    {
-        return isset($this->parts[$name]);
-    }
-
-    /**
-     * @return array
-     */
-    public function getParts()
-    {
-        return $this->parts;
-    }
-
-    /**
-     * Set BorderParts.
-     *
-     * @param array $parts
-     */
-    public function setParts($parts)
-    {
-        $this->parts = [];
-        foreach ($parts as $part) {
-            $this->addPart($part);
+        foreach ($borderParts as $borderPart) {
+            $this->parts[$borderPart->getName()] = $borderPart;
         }
     }
 
-    /**
-     * @return Border
-     */
-    public function addPart(BorderPart $borderPart)
+    public function getPart(string $name): ?BorderPart
     {
-        $this->parts[$borderPart->getName()] = $borderPart;
+        return $this->parts[$name] ?? null;
+    }
 
-        return $this;
+    /**
+     * @return array<string, BorderPart>
+     */
+    public function getParts(): array
+    {
+        return $this->parts;
     }
 }
diff --git a/lib/openspout/src/Common/Entity/Style/BorderPart.php b/lib/openspout/src/Common/Entity/Style/BorderPart.php
index afee7767fc3..e5819e36362 100644
--- a/lib/openspout/src/Common/Entity/Style/BorderPart.php
+++ b/lib/openspout/src/Common/Entity/Style/BorderPart.php
@@ -1,181 +1,90 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Entity\Style;
 
 use OpenSpout\Writer\Exception\Border\InvalidNameException;
 use OpenSpout\Writer\Exception\Border\InvalidStyleException;
 use OpenSpout\Writer\Exception\Border\InvalidWidthException;
 
-class BorderPart
+final class BorderPart
 {
-    /**
-     * @var string the style of this border part
-     */
-    protected $style;
-
-    /**
-     * @var string the name of this border part
-     */
-    protected $name;
-
-    /**
-     * @var string the color of this border part
-     */
-    protected $color;
-
-    /**
-     * @var string the width of this border part
-     */
-    protected $width;
-
-    /**
-     * @var array allowed style constants for parts
-     */
-    protected static $allowedStyles = [
-        'none',
-        'solid',
-        'dashed',
-        'dotted',
-        'double',
+    public const allowedStyles = [
+        Border::STYLE_NONE,
+        Border::STYLE_SOLID,
+        Border::STYLE_DASHED,
+        Border::STYLE_DOTTED,
+        Border::STYLE_DOUBLE,
     ];
 
-    /**
-     * @var array allowed names constants for border parts
-     */
-    protected static $allowedNames = [
-        'left',
-        'right',
-        'top',
-        'bottom',
+    public const allowedNames = [
+        Border::LEFT,
+        Border::RIGHT,
+        Border::TOP,
+        Border::BOTTOM,
     ];
 
-    /**
-     * @var array allowed width constants for border parts
-     */
-    protected static $allowedWidths = [
-        'thin',
-        'medium',
-        'thick',
+    public const allowedWidths = [
+        Border::WIDTH_THIN,
+        Border::WIDTH_MEDIUM,
+        Border::WIDTH_THICK,
     ];
 
+    private string $style;
+    private string $name;
+    private string $color;
+    private string $width;
+
     /**
-     * @param string $name  @see  BorderPart::$allowedNames
+     * @param string $name  @see  BorderPart::allowedNames
      * @param string $color A RGB color code
-     * @param string $width @see BorderPart::$allowedWidths
-     * @param string $style @see BorderPart::$allowedStyles
+     * @param string $width @see BorderPart::allowedWidths
+     * @param string $style @see BorderPart::allowedStyles
      *
      * @throws InvalidNameException
      * @throws InvalidStyleException
      * @throws InvalidWidthException
      */
-    public function __construct($name, $color = Color::BLACK, $width = Border::WIDTH_MEDIUM, $style = Border::STYLE_SOLID)
-    {
-        $this->setName($name);
-        $this->setColor($color);
-        $this->setWidth($width);
-        $this->setStyle($style);
+    public function __construct(
+        string $name,
+        string $color = Color::BLACK,
+        string $width = Border::WIDTH_MEDIUM,
+        string $style = Border::STYLE_SOLID
+    ) {
+        if (!\in_array($name, self::allowedNames, true)) {
+            throw new InvalidNameException($name);
+        }
+        if (!\in_array($style, self::allowedStyles, true)) {
+            throw new InvalidStyleException($style);
+        }
+        if (!\in_array($width, self::allowedWidths, true)) {
+            throw new InvalidWidthException($width);
+        }
+
+        $this->name = $name;
+        $this->color = $color;
+        $this->width = $width;
+        $this->style = $style;
     }
 
-    /**
-     * @return string
-     */
-    public function getName()
+    public function getName(): string
     {
         return $this->name;
     }
 
-    /**
-     * @param string $name The name of the border part @see BorderPart::$allowedNames
-     *
-     * @throws InvalidNameException
-     */
-    public function setName($name)
-    {
-        if (!\in_array($name, self::$allowedNames, true)) {
-            throw new InvalidNameException($name);
-        }
-        $this->name = $name;
-    }
-
-    /**
-     * @return string
-     */
-    public function getStyle()
+    public function getStyle(): string
     {
         return $this->style;
     }
 
-    /**
-     * @param string $style The style of the border part @see BorderPart::$allowedStyles
-     *
-     * @throws InvalidStyleException
-     */
-    public function setStyle($style)
-    {
-        if (!\in_array($style, self::$allowedStyles, true)) {
-            throw new InvalidStyleException($style);
-        }
-        $this->style = $style;
-    }
-
-    /**
-     * @return string
-     */
-    public function getColor()
+    public function getColor(): string
     {
         return $this->color;
     }
 
-    /**
-     * @param string $color The color of the border part @see Color::rgb()
-     */
-    public function setColor($color)
-    {
-        $this->color = $color;
-    }
-
-    /**
-     * @return string
-     */
-    public function getWidth()
+    public function getWidth(): string
     {
         return $this->width;
     }
-
-    /**
-     * @param string $width The width of the border part @see BorderPart::$allowedWidths
-     *
-     * @throws InvalidWidthException
-     */
-    public function setWidth($width)
-    {
-        if (!\in_array($width, self::$allowedWidths, true)) {
-            throw new InvalidWidthException($width);
-        }
-        $this->width = $width;
-    }
-
-    /**
-     * @return array
-     */
-    public static function getAllowedStyles()
-    {
-        return self::$allowedStyles;
-    }
-
-    /**
-     * @return array
-     */
-    public static function getAllowedNames()
-    {
-        return self::$allowedNames;
-    }
-
-    /**
-     * @return array
-     */
-    public static function getAllowedWidths()
-    {
-        return self::$allowedWidths;
-    }
 }
diff --git a/lib/openspout/src/Common/Entity/Style/CellAlignment.php b/lib/openspout/src/Common/Entity/Style/CellAlignment.php
index ecfa6d7f728..48d4da3ad4c 100644
--- a/lib/openspout/src/Common/Entity/Style/CellAlignment.php
+++ b/lib/openspout/src/Common/Entity/Style/CellAlignment.php
@@ -1,18 +1,20 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Entity\Style;
 
 /**
  * This class provides constants to work with text alignment.
  */
-abstract class CellAlignment
+final class CellAlignment
 {
     public const LEFT = 'left';
     public const RIGHT = 'right';
     public const CENTER = 'center';
     public const JUSTIFY = 'justify';
 
-    private static $VALID_ALIGNMENTS = [
+    private const VALID_ALIGNMENTS = [
         self::LEFT => 1,
         self::RIGHT => 1,
         self::CENTER => 1,
@@ -20,12 +22,10 @@ abstract class CellAlignment
     ];
 
     /**
-     * @param string $cellAlignment
-     *
      * @return bool Whether the given cell alignment is valid
      */
-    public static function isValid($cellAlignment)
+    public static function isValid(string $cellAlignment): bool
     {
-        return isset(self::$VALID_ALIGNMENTS[$cellAlignment]);
+        return isset(self::VALID_ALIGNMENTS[$cellAlignment]);
     }
 }
diff --git a/lib/openspout/src/Common/Entity/Style/CellVerticalAlignment.php b/lib/openspout/src/Common/Entity/Style/CellVerticalAlignment.php
new file mode 100644
index 00000000000..2a38fdf6933
--- /dev/null
+++ b/lib/openspout/src/Common/Entity/Style/CellVerticalAlignment.php
@@ -0,0 +1,37 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Entity\Style;
+
+/**
+ * This class provides constants to work with text vertical alignment.
+ */
+final class CellVerticalAlignment
+{
+    public const AUTO = 'auto';
+    public const BASELINE = 'baseline';
+    public const BOTTOM = 'bottom';
+    public const CENTER = 'center';
+    public const DISTRIBUTED = 'distributed';
+    public const JUSTIFY = 'justify';
+    public const TOP = 'top';
+
+    private const VALID_ALIGNMENTS = [
+        self::AUTO => 1,
+        self::BASELINE => 1,
+        self::BOTTOM => 1,
+        self::CENTER => 1,
+        self::DISTRIBUTED => 1,
+        self::JUSTIFY => 1,
+        self::TOP => 1,
+    ];
+
+    /**
+     * @return bool Whether the given cell vertical alignment is valid
+     */
+    public static function isValid(string $cellVerticalAlignment): bool
+    {
+        return isset(self::VALID_ALIGNMENTS[$cellVerticalAlignment]);
+    }
+}
diff --git a/lib/openspout/src/Common/Entity/Style/Color.php b/lib/openspout/src/Common/Entity/Style/Color.php
index cd9bdfd5cfb..4dd5e3e1b48 100644
--- a/lib/openspout/src/Common/Entity/Style/Color.php
+++ b/lib/openspout/src/Common/Entity/Style/Color.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Entity\Style;
 
 use OpenSpout\Common\Exception\InvalidColorException;
@@ -7,9 +9,11 @@ use OpenSpout\Common\Exception\InvalidColorException;
 /**
  * This class provides constants and functions to work with colors.
  */
-abstract class Color
+final class Color
 {
-    /** Standard colors - based on Office Online */
+    /**
+     * Standard colors - based on Office Online.
+     */
     public const BLACK = '000000';
     public const WHITE = 'FFFFFF';
     public const RED = 'FF0000';
@@ -32,7 +36,7 @@ abstract class Color
      *
      * @return string RGB color
      */
-    public static function rgb($red, $green, $blue)
+    public static function rgb(int $red, int $green, int $blue): string
     {
         self::throwIfInvalidColorComponentValue($red);
         self::throwIfInvalidColorComponentValue($green);
@@ -53,7 +57,7 @@ abstract class Color
      *
      * @return string ARGB color
      */
-    public static function toARGB($rgbColor)
+    public static function toARGB(string $rgbColor): string
     {
         return 'FF'.$rgbColor;
     }
@@ -61,13 +65,11 @@ abstract class Color
     /**
      * Throws an exception is the color component value is outside of bounds (0 - 255).
      *
-     * @param int $colorComponent
-     *
      * @throws \OpenSpout\Common\Exception\InvalidColorException
      */
-    protected static function throwIfInvalidColorComponentValue($colorComponent)
+    private static function throwIfInvalidColorComponentValue(int $colorComponent): void
     {
-        if (!\is_int($colorComponent) || $colorComponent < 0 || $colorComponent > 255) {
+        if ($colorComponent < 0 || $colorComponent > 255) {
             throw new InvalidColorException("The RGB components must be between 0 and 255. Received: {$colorComponent}");
         }
     }
@@ -79,7 +81,7 @@ abstract class Color
      *
      * @return string Corresponding hexadecimal value, with a leading 0 if needed. E.g "0f", "2d"
      */
-    protected static function convertColorComponentToHex($colorComponent)
+    private static function convertColorComponentToHex(int $colorComponent): string
     {
         return str_pad(dechex($colorComponent), 2, '0', STR_PAD_LEFT);
     }
diff --git a/lib/openspout/src/Common/Entity/Style/Style.php b/lib/openspout/src/Common/Entity/Style/Style.php
index 28f1597050a..22e4c7ec56b 100644
--- a/lib/openspout/src/Common/Entity/Style/Style.php
+++ b/lib/openspout/src/Common/Entity/Style/Style.php
@@ -1,159 +1,154 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Entity\Style;
 
+use OpenSpout\Common\Exception\InvalidArgumentException;
+
 /**
  * Represents a style to be applied to a cell.
  */
-class Style
+final class Style
 {
-    /** Default values */
+    /**
+     * Default values.
+     */
     public const DEFAULT_FONT_SIZE = 11;
     public const DEFAULT_FONT_COLOR = Color::BLACK;
     public const DEFAULT_FONT_NAME = 'Arial';
 
-    /** @var null|int Style ID */
-    private $id;
+    /** @var int Style ID */
+    private int $id = -1;
 
     /** @var bool Whether the font should be bold */
-    private $fontBold = false;
+    private bool $fontBold = false;
+
     /** @var bool Whether the bold property was set */
-    private $hasSetFontBold = false;
+    private bool $hasSetFontBold = false;
 
     /** @var bool Whether the font should be italic */
-    private $fontItalic = false;
+    private bool $fontItalic = false;
+
     /** @var bool Whether the italic property was set */
-    private $hasSetFontItalic = false;
+    private bool $hasSetFontItalic = false;
 
     /** @var bool Whether the font should be underlined */
-    private $fontUnderline = false;
+    private bool $fontUnderline = false;
+
     /** @var bool Whether the underline property was set */
-    private $hasSetFontUnderline = false;
+    private bool $hasSetFontUnderline = false;
 
     /** @var bool Whether the font should be struck through */
-    private $fontStrikethrough = false;
+    private bool $fontStrikethrough = false;
+
     /** @var bool Whether the strikethrough property was set */
-    private $hasSetFontStrikethrough = false;
+    private bool $hasSetFontStrikethrough = false;
 
     /** @var int Font size */
-    private $fontSize = self::DEFAULT_FONT_SIZE;
+    private int $fontSize = self::DEFAULT_FONT_SIZE;
+
     /** @var bool Whether the font size property was set */
-    private $hasSetFontSize = false;
+    private bool $hasSetFontSize = false;
 
     /** @var string Font color */
-    private $fontColor = self::DEFAULT_FONT_COLOR;
+    private string $fontColor = self::DEFAULT_FONT_COLOR;
+
     /** @var bool Whether the font color property was set */
-    private $hasSetFontColor = false;
+    private bool $hasSetFontColor = false;
 
     /** @var string Font name */
-    private $fontName = self::DEFAULT_FONT_NAME;
+    private string $fontName = self::DEFAULT_FONT_NAME;
+
     /** @var bool Whether the font name property was set */
-    private $hasSetFontName = false;
+    private bool $hasSetFontName = false;
 
     /** @var bool Whether specific font properties should be applied */
-    private $shouldApplyFont = false;
+    private bool $shouldApplyFont = false;
 
     /** @var bool Whether specific cell alignment should be applied */
-    private $shouldApplyCellAlignment = false;
+    private bool $shouldApplyCellAlignment = false;
+
     /** @var string Cell alignment */
-    private $cellAlignment;
+    private string $cellAlignment;
+
     /** @var bool Whether the cell alignment property was set */
-    private $hasSetCellAlignment = false;
+    private bool $hasSetCellAlignment = false;
+
+    /** @var bool Whether specific cell vertical alignment should be applied */
+    private bool $shouldApplyCellVerticalAlignment = false;
+
+    /** @var string Cell vertical alignment */
+    private string $cellVerticalAlignment;
+
+    /** @var bool Whether the cell vertical alignment property was set */
+    private bool $hasSetCellVerticalAlignment = false;
 
     /** @var bool Whether the text should wrap in the cell (useful for long or multi-lines text) */
-    private $shouldWrapText = false;
+    private bool $shouldWrapText = false;
+
     /** @var bool Whether the wrap text property was set */
-    private $hasSetWrapText = false;
+    private bool $hasSetWrapText = false;
 
     /** @var bool Whether the cell should shrink to fit to content */
-    private $shouldShrinkToFit = false;
+    private bool $shouldShrinkToFit = false;
+
     /** @var bool Whether the shouldShrinkToFit text property was set */
-    private $hasSetShrinkToFit = false;
+    private bool $hasSetShrinkToFit = false;
 
-    /** @var null|Border */
-    private $border;
-
-    /** @var bool Whether border properties should be applied */
-    private $shouldApplyBorder = false;
+    private ?Border $border = null;
 
     /** @var null|string Background color */
-    private $backgroundColor;
-
-    /** @var bool */
-    private $hasSetBackgroundColor = false;
+    private ?string $backgroundColor = null;
 
     /** @var null|string Format */
-    private $format;
+    private ?string $format = null;
 
-    /** @var bool */
-    private $hasSetFormat = false;
+    private bool $isRegistered = false;
 
-    /** @var bool */
-    private $isRegistered = false;
+    private bool $isEmpty = true;
 
-    /** @var bool */
-    private $isEmpty = true;
-
-    /**
-     * @return null|int
-     */
-    public function getId()
+    public function __sleep(): array
     {
+        $vars = get_object_vars($this);
+        unset($vars['id'], $vars['isRegistered']);
+
+        return array_keys($vars);
+    }
+
+    public function getId(): int
+    {
+        \assert(0 <= $this->id);
+
         return $this->id;
     }
 
-    /**
-     * @param int $id
-     *
-     * @return Style
-     */
-    public function setId($id)
+    public function setId(int $id): self
     {
         $this->id = $id;
 
         return $this;
     }
 
-    /**
-     * @return null|Border
-     */
-    public function getBorder()
+    public function getBorder(): ?Border
     {
         return $this->border;
     }
 
-    /**
-     * @return Style
-     */
-    public function setBorder(Border $border)
+    public function setBorder(Border $border): self
     {
-        $this->shouldApplyBorder = true;
         $this->border = $border;
         $this->isEmpty = false;
 
         return $this;
     }
 
-    /**
-     * @return bool
-     */
-    public function shouldApplyBorder()
-    {
-        return $this->shouldApplyBorder;
-    }
-
-    /**
-     * @return bool
-     */
-    public function isFontBold()
+    public function isFontBold(): bool
     {
         return $this->fontBold;
     }
 
-    /**
-     * @return Style
-     */
-    public function setFontBold()
+    public function setFontBold(): self
     {
         $this->fontBold = true;
         $this->hasSetFontBold = true;
@@ -163,26 +158,17 @@ class Style
         return $this;
     }
 
-    /**
-     * @return bool
-     */
-    public function hasSetFontBold()
+    public function hasSetFontBold(): bool
     {
         return $this->hasSetFontBold;
     }
 
-    /**
-     * @return bool
-     */
-    public function isFontItalic()
+    public function isFontItalic(): bool
     {
         return $this->fontItalic;
     }
 
-    /**
-     * @return Style
-     */
-    public function setFontItalic()
+    public function setFontItalic(): self
     {
         $this->fontItalic = true;
         $this->hasSetFontItalic = true;
@@ -192,26 +178,17 @@ class Style
         return $this;
     }
 
-    /**
-     * @return bool
-     */
-    public function hasSetFontItalic()
+    public function hasSetFontItalic(): bool
     {
         return $this->hasSetFontItalic;
     }
 
-    /**
-     * @return bool
-     */
-    public function isFontUnderline()
+    public function isFontUnderline(): bool
     {
         return $this->fontUnderline;
     }
 
-    /**
-     * @return Style
-     */
-    public function setFontUnderline()
+    public function setFontUnderline(): self
     {
         $this->fontUnderline = true;
         $this->hasSetFontUnderline = true;
@@ -221,26 +198,17 @@ class Style
         return $this;
     }
 
-    /**
-     * @return bool
-     */
-    public function hasSetFontUnderline()
+    public function hasSetFontUnderline(): bool
     {
         return $this->hasSetFontUnderline;
     }
 
-    /**
-     * @return bool
-     */
-    public function isFontStrikethrough()
+    public function isFontStrikethrough(): bool
     {
         return $this->fontStrikethrough;
     }
 
-    /**
-     * @return Style
-     */
-    public function setFontStrikethrough()
+    public function setFontStrikethrough(): self
     {
         $this->fontStrikethrough = true;
         $this->hasSetFontStrikethrough = true;
@@ -250,28 +218,20 @@ class Style
         return $this;
     }
 
-    /**
-     * @return bool
-     */
-    public function hasSetFontStrikethrough()
+    public function hasSetFontStrikethrough(): bool
     {
         return $this->hasSetFontStrikethrough;
     }
 
-    /**
-     * @return int
-     */
-    public function getFontSize()
+    public function getFontSize(): int
     {
         return $this->fontSize;
     }
 
     /**
      * @param int $fontSize Font size, in pixels
-     *
-     * @return Style
      */
-    public function setFontSize($fontSize)
+    public function setFontSize(int $fontSize): self
     {
         $this->fontSize = $fontSize;
         $this->hasSetFontSize = true;
@@ -281,18 +241,12 @@ class Style
         return $this;
     }
 
-    /**
-     * @return bool
-     */
-    public function hasSetFontSize()
+    public function hasSetFontSize(): bool
     {
         return $this->hasSetFontSize;
     }
 
-    /**
-     * @return string
-     */
-    public function getFontColor()
+    public function getFontColor(): string
     {
         return $this->fontColor;
     }
@@ -301,10 +255,8 @@ class Style
      * Sets the font color.
      *
      * @param string $fontColor ARGB color (@see Color)
-     *
-     * @return Style
      */
-    public function setFontColor($fontColor)
+    public function setFontColor(string $fontColor): self
     {
         $this->fontColor = $fontColor;
         $this->hasSetFontColor = true;
@@ -314,28 +266,20 @@ class Style
         return $this;
     }
 
-    /**
-     * @return bool
-     */
-    public function hasSetFontColor()
+    public function hasSetFontColor(): bool
     {
         return $this->hasSetFontColor;
     }
 
-    /**
-     * @return string
-     */
-    public function getFontName()
+    public function getFontName(): string
     {
         return $this->fontName;
     }
 
     /**
      * @param string $fontName Name of the font to use
-     *
-     * @return Style
      */
-    public function setFontName($fontName)
+    public function setFontName(string $fontName): self
     {
         $this->fontName = $fontName;
         $this->hasSetFontName = true;
@@ -345,29 +289,30 @@ class Style
         return $this;
     }
 
-    /**
-     * @return bool
-     */
-    public function hasSetFontName()
+    public function hasSetFontName(): bool
     {
         return $this->hasSetFontName;
     }
 
-    /**
-     * @return string
-     */
-    public function getCellAlignment()
+    public function getCellAlignment(): string
     {
         return $this->cellAlignment;
     }
 
+    public function getCellVerticalAlignment(): string
+    {
+        return $this->cellVerticalAlignment;
+    }
+
     /**
      * @param string $cellAlignment The cell alignment
-     *
-     * @return Style
      */
-    public function setCellAlignment($cellAlignment)
+    public function setCellAlignment(string $cellAlignment): self
     {
+        if (!CellAlignment::isValid($cellAlignment)) {
+            throw new InvalidArgumentException('Invalid cell alignment value');
+        }
+
         $this->cellAlignment = $cellAlignment;
         $this->hasSetCellAlignment = true;
         $this->shouldApplyCellAlignment = true;
@@ -377,35 +322,54 @@ class Style
     }
 
     /**
-     * @return bool
+     * @param string $cellVerticalAlignment The cell vertical alignment
      */
-    public function hasSetCellAlignment()
+    public function setCellVerticalAlignment(string $cellVerticalAlignment): self
+    {
+        if (!CellVerticalAlignment::isValid($cellVerticalAlignment)) {
+            throw new InvalidArgumentException('Invalid cell vertical alignment value');
+        }
+
+        $this->cellVerticalAlignment = $cellVerticalAlignment;
+        $this->hasSetCellVerticalAlignment = true;
+        $this->shouldApplyCellVerticalAlignment = true;
+        $this->isEmpty = false;
+
+        return $this;
+    }
+
+    public function hasSetCellAlignment(): bool
     {
         return $this->hasSetCellAlignment;
     }
 
+    public function hasSetCellVerticalAlignment(): bool
+    {
+        return $this->hasSetCellVerticalAlignment;
+    }
+
     /**
      * @return bool Whether specific cell alignment should be applied
      */
-    public function shouldApplyCellAlignment()
+    public function shouldApplyCellAlignment(): bool
     {
         return $this->shouldApplyCellAlignment;
     }
 
-    /**
-     * @return bool
-     */
-    public function shouldWrapText()
+    public function shouldApplyCellVerticalAlignment(): bool
+    {
+        return $this->shouldApplyCellVerticalAlignment;
+    }
+
+    public function shouldWrapText(): bool
     {
         return $this->shouldWrapText;
     }
 
     /**
      * @param bool $shouldWrap Should the text be wrapped
-     *
-     * @return Style
      */
-    public function setShouldWrapText($shouldWrap = true)
+    public function setShouldWrapText(bool $shouldWrap = true): self
     {
         $this->shouldWrapText = $shouldWrap;
         $this->hasSetWrapText = true;
@@ -414,10 +378,7 @@ class Style
         return $this;
     }
 
-    /**
-     * @return bool
-     */
-    public function hasSetWrapText()
+    public function hasSetWrapText(): bool
     {
         return $this->hasSetWrapText;
     }
@@ -425,7 +386,7 @@ class Style
     /**
      * @return bool Whether specific font properties should be applied
      */
-    public function shouldApplyFont()
+    public function shouldApplyFont(): bool
     {
         return $this->shouldApplyFont;
     }
@@ -434,66 +395,36 @@ class Style
      * Sets the background color.
      *
      * @param string $color ARGB color (@see Color)
-     *
-     * @return Style
      */
-    public function setBackgroundColor($color)
+    public function setBackgroundColor(string $color): self
     {
-        $this->hasSetBackgroundColor = true;
         $this->backgroundColor = $color;
         $this->isEmpty = false;
 
         return $this;
     }
 
-    /**
-     * @return null|string
-     */
-    public function getBackgroundColor()
+    public function getBackgroundColor(): ?string
     {
         return $this->backgroundColor;
     }
 
-    /**
-     * @return bool Whether the background color should be applied
-     */
-    public function shouldApplyBackgroundColor()
-    {
-        return $this->hasSetBackgroundColor;
-    }
-
     /**
      * Sets format.
-     *
-     * @param string $format
-     *
-     * @return Style
      */
-    public function setFormat($format)
+    public function setFormat(string $format): self
     {
-        $this->hasSetFormat = true;
         $this->format = $format;
         $this->isEmpty = false;
 
         return $this;
     }
 
-    /**
-     * @return null|string
-     */
-    public function getFormat()
+    public function getFormat(): ?string
     {
         return $this->format;
     }
 
-    /**
-     * @return bool Whether format should be applied
-     */
-    public function shouldApplyFormat()
-    {
-        return $this->hasSetFormat;
-    }
-
     public function isRegistered(): bool
     {
         return $this->isRegistered;
@@ -505,12 +436,6 @@ class Style
         $this->isRegistered = true;
     }
 
-    public function unmarkAsRegistered(): void
-    {
-        $this->setId(0);
-        $this->isRegistered = false;
-    }
-
     public function isEmpty(): bool
     {
         return $this->isEmpty;
@@ -518,12 +443,8 @@ class Style
 
     /**
      * Sets should shrink to fit.
-     *
-     * @param bool $shrinkToFit
-     *
-     * @return Style
      */
-    public function setShouldShrinkToFit($shrinkToFit = true)
+    public function setShouldShrinkToFit(bool $shrinkToFit = true): self
     {
         $this->hasSetShrinkToFit = true;
         $this->shouldShrinkToFit = $shrinkToFit;
@@ -534,15 +455,12 @@ class Style
     /**
      * @return bool Whether format should be applied
      */
-    public function shouldShrinkToFit()
+    public function shouldShrinkToFit(): bool
     {
         return $this->shouldShrinkToFit;
     }
 
-    /**
-     * @return bool
-     */
-    public function hasSetShrinkToFit()
+    public function hasSetShrinkToFit(): bool
     {
         return $this->hasSetShrinkToFit;
     }
diff --git a/lib/openspout/src/Common/Exception/EncodingConversionException.php b/lib/openspout/src/Common/Exception/EncodingConversionException.php
index ef0cdc6d80b..0a0fce8847b 100644
--- a/lib/openspout/src/Common/Exception/EncodingConversionException.php
+++ b/lib/openspout/src/Common/Exception/EncodingConversionException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Exception;
 
-class EncodingConversionException extends SpoutException
+final class EncodingConversionException extends OpenSpoutException
 {
 }
diff --git a/lib/openspout/src/Common/Exception/IOException.php b/lib/openspout/src/Common/Exception/IOException.php
index 1b4d4c3727b..b452091e627 100644
--- a/lib/openspout/src/Common/Exception/IOException.php
+++ b/lib/openspout/src/Common/Exception/IOException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Exception;
 
-class IOException extends SpoutException
+final class IOException extends OpenSpoutException
 {
 }
diff --git a/lib/openspout/src/Common/Exception/InvalidArgumentException.php b/lib/openspout/src/Common/Exception/InvalidArgumentException.php
index 6a56ed7a2ec..231881ad8ad 100644
--- a/lib/openspout/src/Common/Exception/InvalidArgumentException.php
+++ b/lib/openspout/src/Common/Exception/InvalidArgumentException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Exception;
 
-class InvalidArgumentException extends SpoutException
+final class InvalidArgumentException extends OpenSpoutException
 {
 }
diff --git a/lib/openspout/src/Common/Exception/InvalidColorException.php b/lib/openspout/src/Common/Exception/InvalidColorException.php
index 3fca9feef85..98882adec5c 100644
--- a/lib/openspout/src/Common/Exception/InvalidColorException.php
+++ b/lib/openspout/src/Common/Exception/InvalidColorException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Exception;
 
-class InvalidColorException extends SpoutException
+final class InvalidColorException extends OpenSpoutException
 {
 }
diff --git a/lib/openspout/src/Common/Exception/OpenSpoutException.php b/lib/openspout/src/Common/Exception/OpenSpoutException.php
new file mode 100644
index 00000000000..9a4596ebe3e
--- /dev/null
+++ b/lib/openspout/src/Common/Exception/OpenSpoutException.php
@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common\Exception;
+
+use Exception;
+
+abstract class OpenSpoutException extends Exception
+{
+}
diff --git a/lib/openspout/src/Common/Exception/SpoutException.php b/lib/openspout/src/Common/Exception/SpoutException.php
deleted file mode 100644
index 54a5c832938..00000000000
--- a/lib/openspout/src/Common/Exception/SpoutException.php
+++ /dev/null
@@ -1,7 +0,0 @@
-<?php
-
-namespace OpenSpout\Common\Exception;
-
-abstract class SpoutException extends \Exception
-{
-}
diff --git a/lib/openspout/src/Common/Exception/UnsupportedTypeException.php b/lib/openspout/src/Common/Exception/UnsupportedTypeException.php
index 7918c634ccd..bcae7218300 100644
--- a/lib/openspout/src/Common/Exception/UnsupportedTypeException.php
+++ b/lib/openspout/src/Common/Exception/UnsupportedTypeException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Exception;
 
-class UnsupportedTypeException extends SpoutException
+final class UnsupportedTypeException extends OpenSpoutException
 {
 }
diff --git a/lib/openspout/src/Common/Helper/CellTypeHelper.php b/lib/openspout/src/Common/Helper/CellTypeHelper.php
deleted file mode 100644
index 77f754cded7..00000000000
--- a/lib/openspout/src/Common/Helper/CellTypeHelper.php
+++ /dev/null
@@ -1,82 +0,0 @@
-<?php
-
-namespace OpenSpout\Common\Helper;
-
-/**
- * This class provides helper functions to determine the type of the cell value.
- */
-class CellTypeHelper
-{
-    /**
-     * @param null|mixed $value
-     *
-     * @return bool Whether the given value is considered "empty"
-     */
-    public static function isEmpty($value)
-    {
-        return null === $value || '' === $value;
-    }
-
-    /**
-     * @param mixed $value
-     *
-     * @return bool Whether the given value is a non empty string
-     */
-    public static function isNonEmptyString($value)
-    {
-        return 'string' === \gettype($value) && '' !== $value;
-    }
-
-    /**
-     * Returns whether the given value is numeric.
-     * A numeric value is from type "integer" or "double" ("float" is not returned by gettype).
-     *
-     * @param mixed $value
-     *
-     * @return bool Whether the given value is numeric
-     */
-    public static function isNumeric($value)
-    {
-        $valueType = \gettype($value);
-
-        return 'integer' === $valueType || 'double' === $valueType;
-    }
-
-    /**
-     * Returns whether the given value is boolean.
-     * "true"/"false" and 0/1 are not booleans.
-     *
-     * @param mixed $value
-     *
-     * @return bool Whether the given value is boolean
-     */
-    public static function isBoolean($value)
-    {
-        return 'boolean' === \gettype($value);
-    }
-
-    /**
-     * Returns whether the given value is a DateTime or DateInterval object.
-     *
-     * @param mixed $value
-     *
-     * @return bool Whether the given value is a DateTime or DateInterval object
-     */
-    public static function isDateTimeOrDateInterval($value)
-    {
-        return
-            $value instanceof \DateTimeInterface
-            || $value instanceof \DateInterval
-        ;
-    }
-
-    /**
-     * @param mixed $value
-     *
-     * @return bool
-     */
-    public static function isFormula($value)
-    {
-        return \is_string($value) && isset($value[0]) && '=' === $value[0];
-    }
-}
diff --git a/lib/openspout/src/Common/Helper/EncodingHelper.php b/lib/openspout/src/Common/Helper/EncodingHelper.php
index 600584930e3..7facf216d97 100644
--- a/lib/openspout/src/Common/Helper/EncodingHelper.php
+++ b/lib/openspout/src/Common/Helper/EncodingHelper.php
@@ -1,40 +1,46 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Helper;
 
+use Error;
 use OpenSpout\Common\Exception\EncodingConversionException;
 
 /**
- * This class provides helper functions to work with encodings.
+ * @internal
  */
-class EncodingHelper
+final class EncodingHelper
 {
-    /** Definition of the encodings that can have a BOM */
+    /**
+     * Definition of the encodings that can have a BOM.
+     */
     public const ENCODING_UTF8 = 'UTF-8';
     public const ENCODING_UTF16_LE = 'UTF-16LE';
     public const ENCODING_UTF16_BE = 'UTF-16BE';
     public const ENCODING_UTF32_LE = 'UTF-32LE';
     public const ENCODING_UTF32_BE = 'UTF-32BE';
 
-    /** Definition of the BOMs for the different encodings */
+    /**
+     * Definition of the BOMs for the different encodings.
+     */
     public const BOM_UTF8 = "\xEF\xBB\xBF";
     public const BOM_UTF16_LE = "\xFF\xFE";
     public const BOM_UTF16_BE = "\xFE\xFF";
     public const BOM_UTF32_LE = "\xFF\xFE\x00\x00";
     public const BOM_UTF32_BE = "\x00\x00\xFE\xFF";
 
-    /** @var \OpenSpout\Common\Helper\GlobalFunctionsHelper Helper to work with global functions */
-    protected $globalFunctionsHelper;
+    /** @var array<string, string> Map representing the encodings supporting BOMs (key) and their associated BOM (value) */
+    private array $supportedEncodingsWithBom;
 
-    /** @var array Map representing the encodings supporting BOMs (key) and their associated BOM (value) */
-    protected $supportedEncodingsWithBom;
+    private bool $canUseIconv;
 
-    /**
-     * @param \OpenSpout\Common\Helper\GlobalFunctionsHelper $globalFunctionsHelper
-     */
-    public function __construct($globalFunctionsHelper)
+    private bool $canUseMbString;
+
+    public function __construct(bool $canUseIconv, bool $canUseMbString)
     {
-        $this->globalFunctionsHelper = $globalFunctionsHelper;
+        $this->canUseIconv = $canUseIconv;
+        $this->canUseMbString = $canUseMbString;
 
         $this->supportedEncodingsWithBom = [
             self::ENCODING_UTF8 => self::BOM_UTF8,
@@ -45,6 +51,14 @@ class EncodingHelper
         ];
     }
 
+    public static function factory(): self
+    {
+        return new self(
+            \function_exists('iconv'),
+            \function_exists('mb_convert_encoding'),
+        );
+    }
+
     /**
      * Returns the number of bytes to use as offset in order to skip the BOM.
      *
@@ -53,7 +67,7 @@ class EncodingHelper
      *
      * @return int Bytes offset to apply to skip the BOM (0 means no BOM)
      */
-    public function getBytesOffsetToSkipBOM($filePointer, $encoding)
+    public function getBytesOffsetToSkipBOM($filePointer, string $encoding): int
     {
         $byteOffsetToSkipBom = 0;
 
@@ -73,11 +87,11 @@ class EncodingHelper
      * @param string $string         Non UTF-8 string to be converted
      * @param string $sourceEncoding The encoding used to encode the source string
      *
-     * @throws \OpenSpout\Common\Exception\EncodingConversionException If conversion is not supported or if the conversion failed
-     *
      * @return string The converted, UTF-8 string
+     *
+     * @throws \OpenSpout\Common\Exception\EncodingConversionException If conversion is not supported or if the conversion failed
      */
-    public function attemptConversionToUTF8($string, $sourceEncoding)
+    public function attemptConversionToUTF8(?string $string, string $sourceEncoding): ?string
     {
         return $this->attemptConversion($string, $sourceEncoding, self::ENCODING_UTF8);
     }
@@ -88,11 +102,11 @@ class EncodingHelper
      * @param string $string         UTF-8 string to be converted
      * @param string $targetEncoding The encoding the string should be re-encoded into
      *
-     * @throws \OpenSpout\Common\Exception\EncodingConversionException If conversion is not supported or if the conversion failed
-     *
      * @return string The converted string, encoded with the given encoding
+     *
+     * @throws \OpenSpout\Common\Exception\EncodingConversionException If conversion is not supported or if the conversion failed
      */
-    public function attemptConversionFromUTF8($string, $targetEncoding)
+    public function attemptConversionFromUTF8(?string $string, string $targetEncoding): ?string
     {
         return $this->attemptConversion($string, self::ENCODING_UTF8, $targetEncoding);
     }
@@ -105,17 +119,17 @@ class EncodingHelper
      *
      * @return bool TRUE if the file has a BOM, FALSE otherwise
      */
-    protected function hasBOM($filePointer, $encoding)
+    private function hasBOM($filePointer, string $encoding): bool
     {
         $hasBOM = false;
 
-        $this->globalFunctionsHelper->rewind($filePointer);
+        rewind($filePointer);
 
         if (\array_key_exists($encoding, $this->supportedEncodingsWithBom)) {
             $potentialBom = $this->supportedEncodingsWithBom[$encoding];
             $numBytesInBom = \strlen($potentialBom);
 
-            $hasBOM = ($this->globalFunctionsHelper->fgets($filePointer, $numBytesInBom + 1) === $potentialBom);
+            $hasBOM = (fgets($filePointer, $numBytesInBom + 1) === $potentialBom);
         }
 
         return $hasBOM;
@@ -129,23 +143,45 @@ class EncodingHelper
      * @param string $sourceEncoding The encoding used to encode the source string
      * @param string $targetEncoding The encoding the string should be re-encoded into
      *
-     * @throws \OpenSpout\Common\Exception\EncodingConversionException If conversion is not supported or if the conversion failed
-     *
      * @return string The converted string, encoded with the given encoding
+     *
+     * @throws \OpenSpout\Common\Exception\EncodingConversionException If conversion is not supported or if the conversion failed
      */
-    protected function attemptConversion($string, $sourceEncoding, $targetEncoding)
+    private function attemptConversion(?string $string, string $sourceEncoding, string $targetEncoding): ?string
     {
         // if source and target encodings are the same, it's a no-op
-        if ($sourceEncoding === $targetEncoding) {
+        if (null === $string || $sourceEncoding === $targetEncoding) {
             return $string;
         }
 
         $convertedString = null;
 
-        if ($this->canUseIconv()) {
-            $convertedString = $this->globalFunctionsHelper->iconv($string, $sourceEncoding, $targetEncoding);
-        } elseif ($this->canUseMbString()) {
-            $convertedString = $this->globalFunctionsHelper->mb_convert_encoding($string, $sourceEncoding, $targetEncoding);
+        if ($this->canUseIconv) {
+            set_error_handler(static function (): bool {
+                return true;
+            });
+
+            $convertedString = iconv($sourceEncoding, $targetEncoding, $string);
+
+            restore_error_handler();
+        } elseif ($this->canUseMbString) {
+            $errorMessage = null;
+            set_error_handler(static function ($nr, $message) use (&$errorMessage): bool {
+                $errorMessage = $message; // @codeCoverageIgnore
+
+                return true; // @codeCoverageIgnore
+            });
+
+            try {
+                $convertedString = mb_convert_encoding($string, $targetEncoding, $sourceEncoding);
+            } catch (Error $error) {
+                $errorMessage = $error->getMessage();
+            }
+
+            restore_error_handler();
+            if (null !== $errorMessage) {
+                $convertedString = false;
+            }
         } else {
             throw new EncodingConversionException("The conversion from {$sourceEncoding} to {$targetEncoding} is not supported. Please install \"iconv\" or \"PHP Intl\".");
         }
@@ -156,25 +192,4 @@ class EncodingHelper
 
         return $convertedString;
     }
-
-    /**
-     * Returns whether "iconv" can be used.
-     *
-     * @return bool TRUE if "iconv" is available and can be used, FALSE otherwise
-     */
-    protected function canUseIconv()
-    {
-        return $this->globalFunctionsHelper->function_exists('iconv');
-    }
-
-    /**
-     * Returns whether "mb_string" functions can be used.
-     * These functions come with the PHP Intl package.
-     *
-     * @return bool TRUE if "mb_string" functions are available and can be used, FALSE otherwise
-     */
-    protected function canUseMbString()
-    {
-        return $this->globalFunctionsHelper->function_exists('mb_convert_encoding');
-    }
 }
diff --git a/lib/openspout/src/Common/Helper/Escaper/CSV.php b/lib/openspout/src/Common/Helper/Escaper/CSV.php
deleted file mode 100644
index d68199af89c..00000000000
--- a/lib/openspout/src/Common/Helper/Escaper/CSV.php
+++ /dev/null
@@ -1,37 +0,0 @@
-<?php
-
-namespace OpenSpout\Common\Helper\Escaper;
-
-/**
- * Provides functions to escape and unescape data for CSV files.
- */
-class CSV implements EscaperInterface
-{
-    /**
-     * Escapes the given string to make it compatible with CSV.
-     *
-     * @codeCoverageIgnore
-     *
-     * @param string $string The string to escape
-     *
-     * @return string The escaped string
-     */
-    public function escape($string)
-    {
-        return $string;
-    }
-
-    /**
-     * Unescapes the given string to make it compatible with CSV.
-     *
-     * @codeCoverageIgnore
-     *
-     * @param string $string The string to unescape
-     *
-     * @return string The unescaped string
-     */
-    public function unescape($string)
-    {
-        return $string;
-    }
-}
diff --git a/lib/openspout/src/Common/Helper/Escaper/EscaperInterface.php b/lib/openspout/src/Common/Helper/Escaper/EscaperInterface.php
index 471a01736e0..7d551ee334f 100644
--- a/lib/openspout/src/Common/Helper/Escaper/EscaperInterface.php
+++ b/lib/openspout/src/Common/Helper/Escaper/EscaperInterface.php
@@ -1,9 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Helper\Escaper;
 
 /**
- * Interface EscaperInterface.
+ * @internal
  */
 interface EscaperInterface
 {
@@ -14,7 +16,7 @@ interface EscaperInterface
      *
      * @return string The escaped string
      */
-    public function escape($string);
+    public function escape(string $string): string;
 
     /**
      * Unescapes the given string to make it compatible with PHP.
@@ -23,5 +25,5 @@ interface EscaperInterface
      *
      * @return string The unescaped string
      */
-    public function unescape($string);
+    public function unescape(string $string): string;
 }
diff --git a/lib/openspout/src/Common/Helper/Escaper/ODS.php b/lib/openspout/src/Common/Helper/Escaper/ODS.php
index 92b661cf96d..010f9cea9a5 100644
--- a/lib/openspout/src/Common/Helper/Escaper/ODS.php
+++ b/lib/openspout/src/Common/Helper/Escaper/ODS.php
@@ -1,11 +1,13 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Helper\Escaper;
 
 /**
- * Provides functions to escape and unescape data for ODS files.
+ * @internal
  */
-class ODS implements EscaperInterface
+final class ODS implements EscaperInterface
 {
     /**
      * Escapes the given string to make it compatible with XLSX.
@@ -14,33 +16,15 @@ class ODS implements EscaperInterface
      *
      * @return string The escaped string
      */
-    public function escape($string)
+    public function escape(string $string): string
     {
-        // @NOTE: Using ENT_QUOTES as XML entities ('<', '>', '&') as well as
-        //        single/double quotes (for XML attributes) need to be encoded.
-        if (\defined('ENT_DISALLOWED')) {
-            /**
-             * 'ENT_DISALLOWED' ensures that invalid characters in the given document type are replaced.
-             * Otherwise control characters like a vertical tab "\v" will make the XML document unreadable by the XML processor.
-             *
-             * @see https://github.com/box/spout/issues/329
-             */
-            $replacedString = htmlspecialchars($string, ENT_QUOTES | ENT_DISALLOWED, 'UTF-8');
-        } else {
-            // We are on hhvm or any other engine that does not support ENT_DISALLOWED.
-            $escapedString = htmlspecialchars($string, ENT_QUOTES, 'UTF-8');
-
-            // control characters values are from 0 to 1F (hex values) in the ASCII table
-            // some characters should not be escaped though: "\t", "\r" and "\n".
-            $regexPattern = '[\x00-\x08'.
-                            // skipping "\t" (0x9) and "\n" (0xA)
-                            '\x0B-\x0C'.
-                            // skipping "\r" (0xD)
-                            '\x0E-\x1F]';
-            $replacedString = preg_replace("/{$regexPattern}/", '�', $escapedString);
-        }
-
-        return $replacedString;
+        /*
+         * 'ENT_DISALLOWED' ensures that invalid characters in the given document type are replaced.
+         * Otherwise control characters like a vertical tab "\v" will make the XML document unreadable by the XML processor.
+         *
+         * @see https://github.com/box/spout/issues/329
+         */
+        return htmlspecialchars($string, ENT_QUOTES | ENT_DISALLOWED, 'UTF-8');
     }
 
     /**
@@ -50,7 +34,7 @@ class ODS implements EscaperInterface
      *
      * @return string The unescaped string
      */
-    public function unescape($string)
+    public function unescape(string $string): string
     {
         // ==============
         // =   WARNING  =
diff --git a/lib/openspout/src/Common/Helper/Escaper/XLSX.php b/lib/openspout/src/Common/Helper/Escaper/XLSX.php
index 16bb162a38f..130ee5f4973 100644
--- a/lib/openspout/src/Common/Helper/Escaper/XLSX.php
+++ b/lib/openspout/src/Common/Helper/Escaper/XLSX.php
@@ -1,23 +1,25 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Helper\Escaper;
 
 /**
- * Provides functions to escape and unescape data for XLSX files.
+ * @internal
  */
-class XLSX implements EscaperInterface
+final class XLSX implements EscaperInterface
 {
     /** @var bool Whether the escaper has already been initialized */
-    private $isAlreadyInitialized = false;
+    private bool $isAlreadyInitialized = false;
 
     /** @var string Regex pattern to detect control characters that need to be escaped */
-    private $escapableControlCharactersPattern;
+    private string $escapableControlCharactersPattern;
 
     /** @var string[] Map containing control characters to be escaped (key) and their escaped value (value) */
-    private $controlCharactersEscapingMap;
+    private array $controlCharactersEscapingMap;
 
     /** @var string[] Map containing control characters to be escaped (value) and their escaped value (key) */
-    private $controlCharactersEscapingReverseMap;
+    private array $controlCharactersEscapingReverseMap;
 
     /**
      * Escapes the given string to make it compatible with XLSX.
@@ -26,7 +28,7 @@ class XLSX implements EscaperInterface
      *
      * @return string The escaped string
      */
-    public function escape($string)
+    public function escape(string $string): string
     {
         $this->initIfNeeded();
 
@@ -43,7 +45,7 @@ class XLSX implements EscaperInterface
      *
      * @return string The unescaped string
      */
-    public function unescape($string)
+    public function unescape(string $string): string
     {
         $this->initIfNeeded();
 
@@ -59,7 +61,7 @@ class XLSX implements EscaperInterface
     /**
      * Initializes the control characters if not already done.
      */
-    protected function initIfNeeded()
+    private function initIfNeeded(): void
     {
         if (!$this->isAlreadyInitialized) {
             $this->escapableControlCharactersPattern = $this->getEscapableControlCharactersPattern();
@@ -73,7 +75,7 @@ class XLSX implements EscaperInterface
     /**
      * @return string Regex pattern containing all escapable control characters
      */
-    protected function getEscapableControlCharactersPattern()
+    private function getEscapableControlCharactersPattern(): string
     {
         // control characters values are from 0 to 1F (hex values) in the ASCII table
         // some characters should not be escaped though: "\t", "\r" and "\n".
@@ -95,14 +97,14 @@ class XLSX implements EscaperInterface
      *
      * @return string[]
      */
-    protected function getControlCharactersEscapingMap()
+    private function getControlCharactersEscapingMap(): array
     {
         $controlCharactersEscapingMap = [];
 
         // control characters values are from 0 to 1F (hex values) in the ASCII table
         for ($charValue = 0x00; $charValue <= 0x1F; ++$charValue) {
             $character = \chr($charValue);
-            if (preg_match("/{$this->escapableControlCharactersPattern}/", $character)) {
+            if (1 === preg_match("/{$this->escapableControlCharactersPattern}/", $character)) {
                 $charHexValue = dechex($charValue);
                 $escapedChar = '_x'.sprintf('%04s', strtoupper($charHexValue)).'_';
                 $controlCharactersEscapingMap[$escapedChar] = $character;
@@ -124,15 +126,13 @@ class XLSX implements EscaperInterface
      * @see https://github.com/jmcnamara/XlsxWriter/blob/f1e610f29/xlsxwriter/sharedstrings.py#L89
      *
      * @param string $string String to escape
-     *
-     * @return string
      */
-    protected function escapeControlCharacters($string)
+    private function escapeControlCharacters(string $string): string
     {
         $escapedString = $this->escapeEscapeCharacter($string);
 
         // if no control characters
-        if (!preg_match("/{$this->escapableControlCharactersPattern}/", $escapedString)) {
+        if (1 !== preg_match("/{$this->escapableControlCharactersPattern}/", $escapedString)) {
             return $escapedString;
         }
 
@@ -148,7 +148,7 @@ class XLSX implements EscaperInterface
      *
      * @return string The escaped string
      */
-    protected function escapeEscapeCharacter($string)
+    private function escapeEscapeCharacter(string $string): string
     {
         return preg_replace('/_(x[\dA-F]{4})_/', '_x005F_$1_', $string);
     }
@@ -165,10 +165,8 @@ class XLSX implements EscaperInterface
      * @see https://github.com/jmcnamara/XlsxWriter/blob/f1e610f29/xlsxwriter/sharedstrings.py#L89
      *
      * @param string $string String to unescape
-     *
-     * @return string
      */
-    protected function unescapeControlCharacters($string)
+    private function unescapeControlCharacters(string $string): string
     {
         $unescapedString = $string;
 
@@ -187,7 +185,7 @@ class XLSX implements EscaperInterface
      *
      * @return string The unescaped string
      */
-    protected function unescapeEscapeCharacter($string)
+    private function unescapeEscapeCharacter(string $string): string
     {
         return preg_replace('/_x005F(_x[\dA-F]{4}_)/', '$1', $string);
     }
diff --git a/lib/openspout/src/Common/Helper/FileSystemHelper.php b/lib/openspout/src/Common/Helper/FileSystemHelper.php
index 130f1f86e47..0fb223bb274 100644
--- a/lib/openspout/src/Common/Helper/FileSystemHelper.php
+++ b/lib/openspout/src/Common/Helper/FileSystemHelper.php
@@ -1,24 +1,34 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Helper;
 
 use OpenSpout\Common\Exception\IOException;
+use RecursiveDirectoryIterator;
+use RecursiveIteratorIterator;
 
 /**
- * This class provides helper functions to help with the file system operations
- * like files/folders creation & deletion.
+ * @internal
  */
-class FileSystemHelper implements FileSystemHelperInterface
+final class FileSystemHelper implements FileSystemHelperInterface
 {
     /** @var string Real path of the base folder where all the I/O can occur */
-    protected $baseFolderRealPath;
+    private string $baseFolderRealPath;
 
     /**
      * @param string $baseFolderPath The path of the base folder where all the I/O can occur
      */
     public function __construct(string $baseFolderPath)
     {
-        $this->baseFolderRealPath = realpath($baseFolderPath);
+        $realpath = realpath($baseFolderPath);
+        \assert(false !== $realpath);
+        $this->baseFolderRealPath = $realpath;
+    }
+
+    public function getBaseFolderRealPath(): string
+    {
+        return $this->baseFolderRealPath;
     }
 
     /**
@@ -27,19 +37,27 @@ class FileSystemHelper implements FileSystemHelperInterface
      * @param string $parentFolderPath The parent folder path under which the folder is going to be created
      * @param string $folderName       The name of the folder to create
      *
-     * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder or if the folder path is not inside of the base folder
-     *
      * @return string Path of the created folder
+     *
+     * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder or if the folder path is not inside of the base folder
      */
-    public function createFolder($parentFolderPath, $folderName)
+    public function createFolder(string $parentFolderPath, string $folderName): string
     {
         $this->throwIfOperationNotInBaseFolder($parentFolderPath);
 
-        $folderPath = $parentFolderPath.'/'.$folderName;
+        $folderPath = $parentFolderPath.\DIRECTORY_SEPARATOR.$folderName;
 
+        $errorMessage = '';
+        set_error_handler(static function ($nr, $message) use (&$errorMessage): bool {
+            $errorMessage = $message;
+
+            return true;
+        });
         $wasCreationSuccessful = mkdir($folderPath, 0777, true);
+        restore_error_handler();
+
         if (!$wasCreationSuccessful) {
-            throw new IOException("Unable to create folder: {$folderPath}");
+            throw new IOException("Unable to create folder: {$folderPath} - {$errorMessage}");
         }
 
         return $folderPath;
@@ -53,19 +71,27 @@ class FileSystemHelper implements FileSystemHelperInterface
      * @param string $fileName         The name of the file to create
      * @param string $fileContents     The contents of the file to create
      *
-     * @throws \OpenSpout\Common\Exception\IOException If unable to create the file or if the file path is not inside of the base folder
-     *
      * @return string Path of the created file
+     *
+     * @throws \OpenSpout\Common\Exception\IOException If unable to create the file or if the file path is not inside of the base folder
      */
-    public function createFileWithContents($parentFolderPath, $fileName, $fileContents)
+    public function createFileWithContents(string $parentFolderPath, string $fileName, string $fileContents): string
     {
         $this->throwIfOperationNotInBaseFolder($parentFolderPath);
 
-        $filePath = $parentFolderPath.'/'.$fileName;
+        $filePath = $parentFolderPath.\DIRECTORY_SEPARATOR.$fileName;
 
+        $errorMessage = '';
+        set_error_handler(static function ($nr, $message) use (&$errorMessage): bool {
+            $errorMessage = $message;
+
+            return true;
+        });
         $wasCreationSuccessful = file_put_contents($filePath, $fileContents);
+        restore_error_handler();
+
         if (false === $wasCreationSuccessful) {
-            throw new IOException("Unable to create file: {$filePath}");
+            throw new IOException("Unable to create file: {$filePath} - {$errorMessage}");
         }
 
         return $filePath;
@@ -78,7 +104,7 @@ class FileSystemHelper implements FileSystemHelperInterface
      *
      * @throws \OpenSpout\Common\Exception\IOException If the file path is not inside of the base folder
      */
-    public function deleteFile($filePath)
+    public function deleteFile(string $filePath): void
     {
         $this->throwIfOperationNotInBaseFolder($filePath);
 
@@ -94,13 +120,13 @@ class FileSystemHelper implements FileSystemHelperInterface
      *
      * @throws \OpenSpout\Common\Exception\IOException If the folder path is not inside of the base folder
      */
-    public function deleteFolderRecursively($folderPath)
+    public function deleteFolderRecursively(string $folderPath): void
     {
         $this->throwIfOperationNotInBaseFolder($folderPath);
 
-        $itemIterator = new \RecursiveIteratorIterator(
-            new \RecursiveDirectoryIterator($folderPath, \RecursiveDirectoryIterator::SKIP_DOTS),
-            \RecursiveIteratorIterator::CHILD_FIRST
+        $itemIterator = new RecursiveIteratorIterator(
+            new RecursiveDirectoryIterator($folderPath, RecursiveDirectoryIterator::SKIP_DOTS),
+            RecursiveIteratorIterator::CHILD_FIRST
         );
 
         foreach ($itemIterator as $item) {
@@ -124,13 +150,13 @@ class FileSystemHelper implements FileSystemHelperInterface
      * @throws \OpenSpout\Common\Exception\IOException If the folder where the I/O operation should occur
      *                                                 is not inside the base folder or the base folder does not exist
      */
-    protected function throwIfOperationNotInBaseFolder(string $operationFolderPath)
+    private function throwIfOperationNotInBaseFolder(string $operationFolderPath): void
     {
         $operationFolderRealPath = realpath($operationFolderPath);
-        if (!$this->baseFolderRealPath) {
-            throw new IOException("The base folder path is invalid: {$this->baseFolderRealPath}");
+        if (false === $operationFolderRealPath) {
+            throw new IOException("Folder not found: {$operationFolderRealPath}");
         }
-        $isInBaseFolder = (0 === strpos($operationFolderRealPath, $this->baseFolderRealPath));
+        $isInBaseFolder = str_starts_with($operationFolderRealPath, $this->baseFolderRealPath);
         if (!$isInBaseFolder) {
             throw new IOException("Cannot perform I/O operation outside of the base folder: {$this->baseFolderRealPath}");
         }
diff --git a/lib/openspout/src/Common/Helper/FileSystemHelperInterface.php b/lib/openspout/src/Common/Helper/FileSystemHelperInterface.php
index 90082d28bf9..a6d12d89fa6 100644
--- a/lib/openspout/src/Common/Helper/FileSystemHelperInterface.php
+++ b/lib/openspout/src/Common/Helper/FileSystemHelperInterface.php
@@ -1,10 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Helper;
 
 /**
- * This interface describes helper functions to help with the file system operations
- * like files/folders creation & deletion.
+ * @internal
  */
 interface FileSystemHelperInterface
 {
@@ -14,11 +15,11 @@ interface FileSystemHelperInterface
      * @param string $parentFolderPath The parent folder path under which the folder is going to be created
      * @param string $folderName       The name of the folder to create
      *
-     * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder or if the folder path is not inside of the base folder
-     *
      * @return string Path of the created folder
+     *
+     * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder or if the folder path is not inside of the base folder
      */
-    public function createFolder($parentFolderPath, $folderName);
+    public function createFolder(string $parentFolderPath, string $folderName): string;
 
     /**
      * Creates a file with the given name and content in the given folder.
@@ -28,11 +29,11 @@ interface FileSystemHelperInterface
      * @param string $fileName         The name of the file to create
      * @param string $fileContents     The contents of the file to create
      *
-     * @throws \OpenSpout\Common\Exception\IOException If unable to create the file or if the file path is not inside of the base folder
-     *
      * @return string Path of the created file
+     *
+     * @throws \OpenSpout\Common\Exception\IOException If unable to create the file or if the file path is not inside of the base folder
      */
-    public function createFileWithContents($parentFolderPath, $fileName, $fileContents);
+    public function createFileWithContents(string $parentFolderPath, string $fileName, string $fileContents): string;
 
     /**
      * Delete the file at the given path.
@@ -41,7 +42,7 @@ interface FileSystemHelperInterface
      *
      * @throws \OpenSpout\Common\Exception\IOException If the file path is not inside of the base folder
      */
-    public function deleteFile($filePath);
+    public function deleteFile(string $filePath): void;
 
     /**
      * Delete the folder at the given path as well as all its contents.
@@ -50,5 +51,5 @@ interface FileSystemHelperInterface
      *
      * @throws \OpenSpout\Common\Exception\IOException If the folder path is not inside of the base folder
      */
-    public function deleteFolderRecursively($folderPath);
+    public function deleteFolderRecursively(string $folderPath): void;
 }
diff --git a/lib/openspout/src/Common/Helper/GlobalFunctionsHelper.php b/lib/openspout/src/Common/Helper/GlobalFunctionsHelper.php
deleted file mode 100644
index 210bc079e6f..00000000000
--- a/lib/openspout/src/Common/Helper/GlobalFunctionsHelper.php
+++ /dev/null
@@ -1,371 +0,0 @@
-<?php
-
-namespace OpenSpout\Common\Helper;
-
-/**
- * This class wraps global functions to facilitate testing.
- *
- * @codeCoverageIgnore
- */
-class GlobalFunctionsHelper
-{
-    /**
-     * Wrapper around global function fopen().
-     *
-     * @see fopen()
-     *
-     * @param string $fileName
-     * @param string $mode
-     *
-     * @return bool|resource
-     */
-    public function fopen($fileName, $mode)
-    {
-        return fopen($fileName, $mode);
-    }
-
-    /**
-     * Wrapper around global function fgets().
-     *
-     * @see fgets()
-     *
-     * @param resource $handle
-     * @param null|int $length
-     *
-     * @return string
-     */
-    public function fgets($handle, $length = null)
-    {
-        return fgets($handle, $length);
-    }
-
-    /**
-     * Wrapper around global function fputs().
-     *
-     * @see fputs()
-     *
-     * @param resource $handle
-     * @param string   $string
-     *
-     * @return int
-     */
-    public function fputs($handle, $string)
-    {
-        return fwrite($handle, $string);
-    }
-
-    /**
-     * Wrapper around global function fflush().
-     *
-     * @see fflush()
-     *
-     * @param resource $handle
-     *
-     * @return bool
-     */
-    public function fflush($handle)
-    {
-        return fflush($handle);
-    }
-
-    /**
-     * Wrapper around global function fseek().
-     *
-     * @see fseek()
-     *
-     * @param resource $handle
-     * @param int      $offset
-     *
-     * @return int
-     */
-    public function fseek($handle, $offset)
-    {
-        return fseek($handle, $offset);
-    }
-
-    /**
-     * Wrapper around global function fgetcsv().
-     *
-     * @see fgetcsv()
-     *
-     * @param resource    $handle
-     * @param null|int    $length
-     * @param null|string $delimiter
-     * @param null|string $enclosure
-     *
-     * @return array|false
-     */
-    public function fgetcsv($handle, $length = null, $delimiter = null, $enclosure = null)
-    {
-        /**
-         * PHP uses '\' as the default escape character. This is not RFC-4180 compliant...
-         * To fix that, simply disable the escape character.
-         *
-         * @see https://bugs.php.net/bug.php?id=43225
-         * @see http://tools.ietf.org/html/rfc4180
-         */
-        $escapeCharacter = \PHP_VERSION_ID >= 70400 ? '' : "\0";
-
-        return fgetcsv($handle, $length, $delimiter, $enclosure, $escapeCharacter);
-    }
-
-    /**
-     * Wrapper around global function fputcsv().
-     *
-     * @see fputcsv()
-     *
-     * @param resource    $handle
-     * @param null|string $delimiter
-     * @param null|string $enclosure
-     *
-     * @return false|int
-     */
-    public function fputcsv($handle, array $fields, $delimiter = null, $enclosure = null)
-    {
-        /**
-         * PHP uses '\' as the default escape character. This is not RFC-4180 compliant...
-         * To fix that, simply disable the escape character.
-         *
-         * @see https://bugs.php.net/bug.php?id=43225
-         * @see http://tools.ietf.org/html/rfc4180
-         */
-        $escapeCharacter = \PHP_VERSION_ID >= 70400 ? '' : "\0";
-
-        return fputcsv($handle, $fields, $delimiter, $enclosure, $escapeCharacter);
-    }
-
-    /**
-     * Wrapper around global function fwrite().
-     *
-     * @see fwrite()
-     *
-     * @param resource $handle
-     * @param string   $string
-     *
-     * @return int
-     */
-    public function fwrite($handle, $string)
-    {
-        return fwrite($handle, $string);
-    }
-
-    /**
-     * Wrapper around global function fclose().
-     *
-     * @see fclose()
-     *
-     * @param resource $handle
-     *
-     * @return bool
-     */
-    public function fclose($handle)
-    {
-        return fclose($handle);
-    }
-
-    /**
-     * Wrapper around global function rewind().
-     *
-     * @see rewind()
-     *
-     * @param resource $handle
-     *
-     * @return bool
-     */
-    public function rewind($handle)
-    {
-        return rewind($handle);
-    }
-
-    /**
-     * Wrapper around global function file_exists().
-     *
-     * @see file_exists()
-     *
-     * @param string $fileName
-     *
-     * @return bool
-     */
-    public function file_exists($fileName)
-    {
-        return file_exists($fileName);
-    }
-
-    /**
-     * Wrapper around global function file_get_contents().
-     *
-     * @see file_get_contents()
-     *
-     * @param string $filePath
-     *
-     * @return string
-     */
-    public function file_get_contents($filePath)
-    {
-        $realFilePath = $this->convertToUseRealPath($filePath);
-
-        return file_get_contents($realFilePath);
-    }
-
-    /**
-     * Wrapper around global function feof().
-     *
-     * @see feof()
-     *
-     * @param resource $handle
-     *
-     * @return bool
-     */
-    public function feof($handle)
-    {
-        return feof($handle);
-    }
-
-    /**
-     * Wrapper around global function is_readable().
-     *
-     * @see is_readable()
-     *
-     * @param string $fileName
-     *
-     * @return bool
-     */
-    public function is_readable($fileName)
-    {
-        return is_readable($fileName);
-    }
-
-    /**
-     * Wrapper around global function basename().
-     *
-     * @see basename()
-     *
-     * @param string $path
-     * @param string $suffix
-     *
-     * @return string
-     */
-    public function basename($path, $suffix = '')
-    {
-        return basename($path, $suffix);
-    }
-
-    /**
-     * Wrapper around global function header().
-     *
-     * @see header()
-     *
-     * @param string $string
-     */
-    public function header($string)
-    {
-        header($string);
-    }
-
-    /**
-     * Wrapper around global function ob_end_clean().
-     *
-     * @see ob_end_clean()
-     */
-    public function ob_end_clean()
-    {
-        if (ob_get_length() > 0) {
-            ob_end_clean();
-        }
-    }
-
-    /**
-     * Wrapper around global function iconv().
-     *
-     * @see iconv()
-     *
-     * @param string $string         The string to be converted
-     * @param string $sourceEncoding The encoding of the source string
-     * @param string $targetEncoding The encoding the source string should be converted to
-     *
-     * @return bool|string the converted string or FALSE on failure
-     */
-    public function iconv($string, $sourceEncoding, $targetEncoding)
-    {
-        return iconv($sourceEncoding, $targetEncoding, $string);
-    }
-
-    /**
-     * Wrapper around global function mb_convert_encoding().
-     *
-     * @see mb_convert_encoding()
-     *
-     * @param string $string         The string to be converted
-     * @param string $sourceEncoding The encoding of the source string
-     * @param string $targetEncoding The encoding the source string should be converted to
-     *
-     * @return bool|string the converted string or FALSE on failure
-     */
-    public function mb_convert_encoding($string, $sourceEncoding, $targetEncoding)
-    {
-        return mb_convert_encoding($string, $targetEncoding, $sourceEncoding);
-    }
-
-    /**
-     * Wrapper around global function stream_get_wrappers().
-     *
-     * @see stream_get_wrappers()
-     *
-     * @return array
-     */
-    public function stream_get_wrappers()
-    {
-        return stream_get_wrappers();
-    }
-
-    /**
-     * Wrapper around global function function_exists().
-     *
-     * @see function_exists()
-     *
-     * @param string $functionName
-     *
-     * @return bool
-     */
-    public function function_exists($functionName)
-    {
-        return \function_exists($functionName);
-    }
-
-    /**
-     * Updates the given file path to use a real path.
-     * This is to avoid issues on some Windows setup.
-     *
-     * @param string $filePath File path
-     *
-     * @return string The file path using a real path
-     */
-    protected function convertToUseRealPath($filePath)
-    {
-        $realFilePath = $filePath;
-
-        if ($this->isZipStream($filePath)) {
-            if (preg_match('/zip:\/\/(.*)#(.*)/', $filePath, $matches)) {
-                $documentPath = $matches[1];
-                $documentInsideZipPath = $matches[2];
-                $realFilePath = 'zip://'.realpath($documentPath).'#'.$documentInsideZipPath;
-            }
-        } else {
-            $realFilePath = realpath($filePath);
-        }
-
-        return $realFilePath;
-    }
-
-    /**
-     * Returns whether the given path is a zip stream.
-     *
-     * @param string $path Path pointing to a document
-     *
-     * @return bool TRUE if path is a zip stream, FALSE otherwise
-     */
-    protected function isZipStream($path)
-    {
-        return 0 === strpos($path, 'zip://');
-    }
-}
diff --git a/lib/openspout/src/Common/Helper/StringHelper.php b/lib/openspout/src/Common/Helper/StringHelper.php
index 96e7f2c3a1c..310d4243042 100644
--- a/lib/openspout/src/Common/Helper/StringHelper.php
+++ b/lib/openspout/src/Common/Helper/StringHelper.php
@@ -1,28 +1,25 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Common\Helper;
 
 /**
- * This class provides helper functions to work with strings and multibyte strings.
- *
- * @codeCoverageIgnore
+ * @internal
  */
-class StringHelper
+final class StringHelper
 {
     /** @var bool Whether the mbstring extension is loaded */
-    protected $hasMbstringSupport;
+    private bool $hasMbstringSupport;
 
-    /** @var bool Whether the code is running with PHP7 or older versions */
-    private $isRunningPhp7OrOlder;
-
-    /** @var array Locale info, used for number formatting */
-    private $localeInfo;
-
-    public function __construct()
+    public function __construct(bool $hasMbstringSupport)
     {
-        $this->hasMbstringSupport = \extension_loaded('mbstring');
-        $this->isRunningPhp7OrOlder = version_compare(PHP_VERSION, '8.0.0') < 0;
-        $this->localeInfo = localeconv();
+        $this->hasMbstringSupport = $hasMbstringSupport;
+    }
+
+    public static function factory(): self
+    {
+        return new self(\function_exists('mb_strlen'));
     }
 
     /**
@@ -31,14 +28,13 @@ class StringHelper
      *
      * @see strlen
      * @see mb_strlen
-     *
-     * @param string $string
-     *
-     * @return int
      */
-    public function getStringLength($string)
+    public function getStringLength(string $string): int
     {
-        return $this->hasMbstringSupport ? mb_strlen($string) : \strlen($string);
+        return $this->hasMbstringSupport
+            ? mb_strlen($string)
+            : \strlen($string) // @codeCoverageIgnore
+        ;
     }
 
     /**
@@ -53,9 +49,12 @@ class StringHelper
      *
      * @return int Char/substring's first occurrence position within the string if found (starts at 0) or -1 if not found
      */
-    public function getCharFirstOccurrencePosition($char, $string)
+    public function getCharFirstOccurrencePosition(string $char, string $string): int
     {
-        $position = $this->hasMbstringSupport ? mb_strpos($string, $char) : strpos($string, $char);
+        $position = $this->hasMbstringSupport
+            ? mb_strpos($string, $char)
+            : strpos($string, $char) // @codeCoverageIgnore
+        ;
 
         return (false !== $position) ? $position : -1;
     }
@@ -72,37 +71,13 @@ class StringHelper
      *
      * @return int Char/substring's last occurrence position within the string if found (starts at 0) or -1 if not found
      */
-    public function getCharLastOccurrencePosition($char, $string)
+    public function getCharLastOccurrencePosition(string $char, string $string): int
     {
-        $position = $this->hasMbstringSupport ? mb_strrpos($string, $char) : strrpos($string, $char);
+        $position = $this->hasMbstringSupport
+            ? mb_strrpos($string, $char)
+            : strrpos($string, $char) // @codeCoverageIgnore
+        ;
 
         return (false !== $position) ? $position : -1;
     }
-
-    /**
-     * Formats a numeric value (int or float) in a way that's compatible with the expected spreadsheet format.
-     *
-     * Formatting of float values is locale dependent in PHP < 8.
-     * Thousands separators and decimal points vary from locale to locale (en_US: 12.34 vs pl_PL: 12,34).
-     * However, float values must be formatted with no thousands separator and a "." as decimal point
-     * to work properly. This method can be used to convert the value to the correct format before storing it.
-     *
-     * @see https://wiki.php.net/rfc/locale_independent_float_to_string for the changed behavior in PHP8.
-     *
-     * @param float|int $numericValue
-     *
-     * @return float|int|string
-     */
-    public function formatNumericValue($numericValue)
-    {
-        if ($this->isRunningPhp7OrOlder && \is_float($numericValue)) {
-            return str_replace(
-                [$this->localeInfo['thousands_sep'], $this->localeInfo['decimal_point']],
-                ['', '.'],
-                (string) $numericValue
-            );
-        }
-
-        return $numericValue;
-    }
 }
diff --git a/lib/openspout/src/Common/Manager/OptionsManagerAbstract.php b/lib/openspout/src/Common/Manager/OptionsManagerAbstract.php
deleted file mode 100644
index 3bfce395ccf..00000000000
--- a/lib/openspout/src/Common/Manager/OptionsManagerAbstract.php
+++ /dev/null
@@ -1,82 +0,0 @@
-<?php
-
-namespace OpenSpout\Common\Manager;
-
-abstract class OptionsManagerAbstract implements OptionsManagerInterface
-{
-    public const PREFIX_OPTION = 'OPTION_';
-
-    /** @var string[] List of all supported option names */
-    private $supportedOptions = [];
-
-    /** @var array Associative array [OPTION_NAME => OPTION_VALUE] */
-    private $options = [];
-
-    /**
-     * OptionsManagerAbstract constructor.
-     */
-    public function __construct()
-    {
-        $this->supportedOptions = $this->getSupportedOptions();
-        $this->setDefaultOptions();
-    }
-
-    /**
-     * Sets the given option, if this option is supported.
-     *
-     * @param string $optionName
-     * @param mixed  $optionValue
-     */
-    public function setOption($optionName, $optionValue)
-    {
-        if (\in_array($optionName, $this->supportedOptions, true)) {
-            $this->options[$optionName] = $optionValue;
-        }
-    }
-
-    /**
-     * Add an option to the internal list of options
-     * Used only for mergeCells() for now.
-     *
-     * @param mixed $optionName
-     * @param mixed $optionValue
-     */
-    public function addOption($optionName, $optionValue)
-    {
-        if (\in_array($optionName, $this->supportedOptions, true)) {
-            if (!isset($this->options[$optionName])) {
-                $this->options[$optionName] = [];
-            } elseif (!\is_array($this->options[$optionName])) {
-                $this->options[$optionName] = [$this->options[$optionName]];
-            }
-            $this->options[$optionName][] = $optionValue;
-        }
-    }
-
-    /**
-     * @param string $optionName
-     *
-     * @return null|mixed The set option or NULL if no option with given name found
-     */
-    public function getOption($optionName)
-    {
-        $optionValue = null;
-
-        if (isset($this->options[$optionName])) {
-            $optionValue = $this->options[$optionName];
-        }
-
-        return $optionValue;
-    }
-
-    /**
-     * @return array List of supported options
-     */
-    abstract protected function getSupportedOptions();
-
-    /**
-     * Sets the default options.
-     * To be overriden by child classes.
-     */
-    abstract protected function setDefaultOptions();
-}
diff --git a/lib/openspout/src/Common/Manager/OptionsManagerInterface.php b/lib/openspout/src/Common/Manager/OptionsManagerInterface.php
deleted file mode 100644
index 7913017a50c..00000000000
--- a/lib/openspout/src/Common/Manager/OptionsManagerInterface.php
+++ /dev/null
@@ -1,31 +0,0 @@
-<?php
-
-namespace OpenSpout\Common\Manager;
-
-/**
- * Interface OptionsManagerInterface.
- */
-interface OptionsManagerInterface
-{
-    /**
-     * @param string $optionName
-     * @param mixed  $optionValue
-     */
-    public function setOption($optionName, $optionValue);
-
-    /**
-     * @param string $optionName
-     *
-     * @return null|mixed The set option or NULL if no option with given name found
-     */
-    public function getOption($optionName);
-
-    /**
-     * Add an option to the internal list of options
-     * Used only for mergeCells() for now.
-     *
-     * @param mixed $optionName
-     * @param mixed $optionValue
-     */
-    public function addOption($optionName, $optionValue);
-}
diff --git a/lib/openspout/src/Common/TempFolderOptionTrait.php b/lib/openspout/src/Common/TempFolderOptionTrait.php
new file mode 100644
index 00000000000..a8d03e48f20
--- /dev/null
+++ b/lib/openspout/src/Common/TempFolderOptionTrait.php
@@ -0,0 +1,33 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Common;
+
+use OpenSpout\Common\Exception\InvalidArgumentException;
+
+/**
+ * @internal
+ */
+trait TempFolderOptionTrait
+{
+    private string $tempFolder;
+
+    final public function setTempFolder(string $tempFolder): void
+    {
+        if (!is_dir($tempFolder) || !is_writable($tempFolder)) {
+            throw new InvalidArgumentException("{$tempFolder} is not a writable folder");
+        }
+
+        $this->tempFolder = $tempFolder;
+    }
+
+    final public function getTempFolder(): string
+    {
+        if (!isset($this->tempFolder)) {
+            $this->setTempFolder(sys_get_temp_dir());
+        }
+
+        return $this->tempFolder;
+    }
+}
diff --git a/lib/openspout/src/Common/Type.php b/lib/openspout/src/Common/Type.php
deleted file mode 100644
index 9c1573d4d59..00000000000
--- a/lib/openspout/src/Common/Type.php
+++ /dev/null
@@ -1,13 +0,0 @@
-<?php
-
-namespace OpenSpout\Common;
-
-/**
- * This class references the supported types.
- */
-abstract class Type
-{
-    public const CSV = 'csv';
-    public const XLSX = 'xlsx';
-    public const ODS = 'ods';
-}
diff --git a/lib/openspout/src/Reader/ReaderAbstract.php b/lib/openspout/src/Reader/AbstractReader.php
similarity index 52%
rename from lib/openspout/src/Reader/ReaderAbstract.php
rename to lib/openspout/src/Reader/AbstractReader.php
index 2b7c8b4e244..3afa0cef6b0 100644
--- a/lib/openspout/src/Reader/ReaderAbstract.php
+++ b/lib/openspout/src/Reader/AbstractReader.php
@@ -1,65 +1,22 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader;
 
 use OpenSpout\Common\Exception\IOException;
-use OpenSpout\Common\Helper\GlobalFunctionsHelper;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Reader\Common\Creator\InternalEntityFactoryInterface;
-use OpenSpout\Reader\Common\Entity\Options;
+use OpenSpout\Reader\Exception\ReaderException;
 use OpenSpout\Reader\Exception\ReaderNotOpenedException;
 
-abstract class ReaderAbstract implements ReaderInterface
+/**
+ * @template T of SheetIteratorInterface
+ *
+ * @implements ReaderInterface<T>
+ */
+abstract class AbstractReader implements ReaderInterface
 {
     /** @var bool Indicates whether the stream is currently open */
-    protected $isStreamOpened = false;
-
-    /** @var InternalEntityFactoryInterface Factory to create entities */
-    protected $entityFactory;
-
-    /** @var \OpenSpout\Common\Helper\GlobalFunctionsHelper Helper to work with global functions */
-    protected $globalFunctionsHelper;
-
-    /** @var OptionsManagerInterface Writer options manager */
-    protected $optionsManager;
-
-    public function __construct(
-        OptionsManagerInterface $optionsManager,
-        GlobalFunctionsHelper $globalFunctionsHelper,
-        InternalEntityFactoryInterface $entityFactory
-    ) {
-        $this->optionsManager = $optionsManager;
-        $this->globalFunctionsHelper = $globalFunctionsHelper;
-        $this->entityFactory = $entityFactory;
-    }
-
-    /**
-     * Sets whether date/time values should be returned as PHP objects or be formatted as strings.
-     *
-     * @param bool $shouldFormatDates
-     *
-     * @return ReaderAbstract
-     */
-    public function setShouldFormatDates($shouldFormatDates)
-    {
-        $this->optionsManager->setOption(Options::SHOULD_FORMAT_DATES, $shouldFormatDates);
-
-        return $this;
-    }
-
-    /**
-     * Sets whether empty rows should be returned or skipped.
-     *
-     * @param bool $shouldPreserveEmptyRows
-     *
-     * @return ReaderAbstract
-     */
-    public function setShouldPreserveEmptyRows($shouldPreserveEmptyRows)
-    {
-        $this->optionsManager->setOption(Options::SHOULD_PRESERVE_EMPTY_ROWS, $shouldPreserveEmptyRows);
-
-        return $this;
-    }
+    private bool $isStreamOpened = false;
 
     /**
      * Prepares the reader to read the given file. It also makes sure
@@ -69,7 +26,7 @@ abstract class ReaderAbstract implements ReaderInterface
      *
      * @throws \OpenSpout\Common\Exception\IOException If the file at the given path does not exist, is not readable or is corrupted
      */
-    public function open($filePath)
+    public function open(string $filePath): void
     {
         if ($this->isStreamWrapper($filePath) && (!$this->doesSupportStreamWrapper() || !$this->isSupportedStreamWrapper($filePath))) {
             throw new IOException("Could not open {$filePath} for reading! Stream wrapper used is not supported for this type of file.");
@@ -77,10 +34,10 @@ abstract class ReaderAbstract implements ReaderInterface
 
         if (!$this->isPhpStream($filePath)) {
             // we skip the checks if the provided file path points to a PHP stream
-            if (!$this->globalFunctionsHelper->file_exists($filePath)) {
+            if (!file_exists($filePath)) {
                 throw new IOException("Could not open {$filePath} for reading! File does not exist.");
             }
-            if (!$this->globalFunctionsHelper->is_readable($filePath)) {
+            if (!is_readable($filePath)) {
                 throw new IOException("Could not open {$filePath} for reading! File is not readable.");
             }
         }
@@ -89,86 +46,66 @@ abstract class ReaderAbstract implements ReaderInterface
             $fileRealPath = $this->getFileRealPath($filePath);
             $this->openReader($fileRealPath);
             $this->isStreamOpened = true;
-        } catch (\Exception $exception) {
-            throw new IOException("Could not open {$filePath} for reading! ({$exception->getMessage()})");
+        } catch (ReaderException $exception) {
+            throw new IOException(
+                "Could not open {$filePath} for reading!",
+                0,
+                $exception
+            );
         }
     }
 
-    /**
-     * Returns an iterator to iterate over sheets.
-     *
-     * @throws \OpenSpout\Reader\Exception\ReaderNotOpenedException If called before opening the reader
-     *
-     * @return SheetIteratorInterface To iterate over sheets
-     */
-    public function getSheetIterator()
-    {
-        if (!$this->isStreamOpened) {
-            throw new ReaderNotOpenedException('Reader should be opened first.');
-        }
-
-        return $this->getConcreteSheetIterator();
-    }
-
     /**
      * Closes the reader, preventing any additional reading.
      */
-    public function close()
+    final public function close(): void
     {
         if ($this->isStreamOpened) {
             $this->closeReader();
 
-            $sheetIterator = $this->getConcreteSheetIterator();
-            if (null !== $sheetIterator) {
-                $sheetIterator->end();
-            }
-
             $this->isStreamOpened = false;
         }
     }
 
     /**
      * Returns whether stream wrappers are supported.
-     *
-     * @return bool
      */
-    abstract protected function doesSupportStreamWrapper();
+    abstract protected function doesSupportStreamWrapper(): bool;
 
     /**
      * Opens the file at the given file path to make it ready to be read.
      *
      * @param string $filePath Path of the file to be read
      */
-    abstract protected function openReader($filePath);
-
-    /**
-     * Returns an iterator to iterate over sheets.
-     *
-     * @return SheetIteratorInterface To iterate over sheets
-     */
-    abstract protected function getConcreteSheetIterator();
+    abstract protected function openReader(string $filePath): void;
 
     /**
      * Closes the reader. To be used after reading the file.
      */
-    abstract protected function closeReader();
+    abstract protected function closeReader(): void;
+
+    final protected function ensureStreamOpened(): void
+    {
+        if (!$this->isStreamOpened) {
+            throw new ReaderNotOpenedException('Reader should be opened first.');
+        }
+    }
 
     /**
      * Returns the real path of the given path.
      * If the given path is a valid stream wrapper, returns the path unchanged.
-     *
-     * @param string $filePath
-     *
-     * @return string
      */
-    protected function getFileRealPath($filePath)
+    private function getFileRealPath(string $filePath): string
     {
         if ($this->isSupportedStreamWrapper($filePath)) {
             return $filePath;
         }
 
         // Need to use realpath to fix "Can't open file" on some Windows setup
-        return realpath($filePath);
+        $realpath = realpath($filePath);
+        \assert(false !== $realpath);
+
+        return $realpath;
     }
 
     /**
@@ -179,10 +116,10 @@ abstract class ReaderAbstract implements ReaderInterface
      *
      * @return null|string The stream wrapper scheme or NULL if not a stream wrapper
      */
-    protected function getStreamWrapperScheme($filePath)
+    private function getStreamWrapperScheme(string $filePath): ?string
     {
         $streamScheme = null;
-        if (preg_match('/^(\w+):\/\//', $filePath, $matches)) {
+        if (1 === preg_match('/^(\w+):\/\//', $filePath, $matches)) {
             $streamScheme = $matches[1];
         }
 
@@ -197,7 +134,7 @@ abstract class ReaderAbstract implements ReaderInterface
      *
      * @return bool Whether the given path is an unsupported stream wrapper
      */
-    protected function isStreamWrapper($filePath)
+    private function isStreamWrapper(string $filePath): bool
     {
         return null !== $this->getStreamWrapperScheme($filePath);
     }
@@ -211,13 +148,11 @@ abstract class ReaderAbstract implements ReaderInterface
      *
      * @return bool Whether the given path is an supported stream wrapper
      */
-    protected function isSupportedStreamWrapper($filePath)
+    private function isSupportedStreamWrapper(string $filePath): bool
     {
         $streamScheme = $this->getStreamWrapperScheme($filePath);
 
-        return (null !== $streamScheme) ?
-            \in_array($streamScheme, $this->globalFunctionsHelper->stream_get_wrappers(), true) :
-            true;
+        return null === $streamScheme || \in_array($streamScheme, stream_get_wrappers(), true);
     }
 
     /**
@@ -227,7 +162,7 @@ abstract class ReaderAbstract implements ReaderInterface
      *
      * @return bool Whether the given path maps to a PHP stream
      */
-    protected function isPhpStream($filePath)
+    private function isPhpStream(string $filePath): bool
     {
         $streamScheme = $this->getStreamWrapperScheme($filePath);
 
diff --git a/lib/openspout/src/Reader/CSV/Creator/InternalEntityFactory.php b/lib/openspout/src/Reader/CSV/Creator/InternalEntityFactory.php
deleted file mode 100644
index 8b3562d19a4..00000000000
--- a/lib/openspout/src/Reader/CSV/Creator/InternalEntityFactory.php
+++ /dev/null
@@ -1,98 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\CSV\Creator;
-
-use OpenSpout\Common\Creator\HelperFactory;
-use OpenSpout\Common\Entity\Cell;
-use OpenSpout\Common\Entity\Row;
-use OpenSpout\Common\Helper\GlobalFunctionsHelper;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Reader\Common\Creator\InternalEntityFactoryInterface;
-use OpenSpout\Reader\CSV\RowIterator;
-use OpenSpout\Reader\CSV\Sheet;
-use OpenSpout\Reader\CSV\SheetIterator;
-
-/**
- * Factory to create entities.
- */
-class InternalEntityFactory implements InternalEntityFactoryInterface
-{
-    /** @var HelperFactory */
-    private $helperFactory;
-
-    public function __construct(HelperFactory $helperFactory)
-    {
-        $this->helperFactory = $helperFactory;
-    }
-
-    /**
-     * @param resource                $filePointer           Pointer to the CSV file to read
-     * @param OptionsManagerInterface $optionsManager
-     * @param GlobalFunctionsHelper   $globalFunctionsHelper
-     *
-     * @return SheetIterator
-     */
-    public function createSheetIterator($filePointer, $optionsManager, $globalFunctionsHelper)
-    {
-        $rowIterator = $this->createRowIterator($filePointer, $optionsManager, $globalFunctionsHelper);
-        $sheet = $this->createSheet($rowIterator);
-
-        return new SheetIterator($sheet);
-    }
-
-    /**
-     * @param Cell[] $cells
-     *
-     * @return Row
-     */
-    public function createRow(array $cells = [])
-    {
-        return new Row($cells, null);
-    }
-
-    /**
-     * @param mixed $cellValue
-     *
-     * @return Cell
-     */
-    public function createCell($cellValue)
-    {
-        return new Cell($cellValue);
-    }
-
-    /**
-     * @return Row
-     */
-    public function createRowFromArray(array $cellValues = [])
-    {
-        $cells = array_map(function ($cellValue) {
-            return $this->createCell($cellValue);
-        }, $cellValues);
-
-        return $this->createRow($cells);
-    }
-
-    /**
-     * @param RowIterator $rowIterator
-     *
-     * @return Sheet
-     */
-    private function createSheet($rowIterator)
-    {
-        return new Sheet($rowIterator);
-    }
-
-    /**
-     * @param resource                $filePointer           Pointer to the CSV file to read
-     * @param OptionsManagerInterface $optionsManager
-     * @param GlobalFunctionsHelper   $globalFunctionsHelper
-     *
-     * @return RowIterator
-     */
-    private function createRowIterator($filePointer, $optionsManager, $globalFunctionsHelper)
-    {
-        $encodingHelper = $this->helperFactory->createEncodingHelper($globalFunctionsHelper);
-
-        return new RowIterator($filePointer, $optionsManager, $encodingHelper, $this, $globalFunctionsHelper);
-    }
-}
diff --git a/lib/openspout/src/Reader/CSV/Manager/OptionsManager.php b/lib/openspout/src/Reader/CSV/Manager/OptionsManager.php
deleted file mode 100644
index 9772a43815c..00000000000
--- a/lib/openspout/src/Reader/CSV/Manager/OptionsManager.php
+++ /dev/null
@@ -1,39 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\CSV\Manager;
-
-use OpenSpout\Common\Helper\EncodingHelper;
-use OpenSpout\Common\Manager\OptionsManagerAbstract;
-use OpenSpout\Reader\Common\Entity\Options;
-
-/**
- * CSV Reader options manager.
- */
-class OptionsManager extends OptionsManagerAbstract
-{
-    /**
-     * {@inheritdoc}
-     */
-    protected function getSupportedOptions()
-    {
-        return [
-            Options::SHOULD_FORMAT_DATES,
-            Options::SHOULD_PRESERVE_EMPTY_ROWS,
-            Options::FIELD_DELIMITER,
-            Options::FIELD_ENCLOSURE,
-            Options::ENCODING,
-        ];
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function setDefaultOptions()
-    {
-        $this->setOption(Options::SHOULD_FORMAT_DATES, false);
-        $this->setOption(Options::SHOULD_PRESERVE_EMPTY_ROWS, false);
-        $this->setOption(Options::FIELD_DELIMITER, ',');
-        $this->setOption(Options::FIELD_ENCLOSURE, '"');
-        $this->setOption(Options::ENCODING, EncodingHelper::ENCODING_UTF8);
-    }
-}
diff --git a/lib/openspout/src/Reader/CSV/Options.php b/lib/openspout/src/Reader/CSV/Options.php
new file mode 100644
index 00000000000..e470915f13d
--- /dev/null
+++ b/lib/openspout/src/Reader/CSV/Options.php
@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Reader\CSV;
+
+use OpenSpout\Common\Helper\EncodingHelper;
+
+final class Options
+{
+    public bool $SHOULD_PRESERVE_EMPTY_ROWS = false;
+    public string $FIELD_DELIMITER = ',';
+    public string $FIELD_ENCLOSURE = '"';
+    public string $ENCODING = EncodingHelper::ENCODING_UTF8;
+}
diff --git a/lib/openspout/src/Reader/CSV/Reader.php b/lib/openspout/src/Reader/CSV/Reader.php
index d62b9330562..ac92b53e2aa 100644
--- a/lib/openspout/src/Reader/CSV/Reader.php
+++ b/lib/openspout/src/Reader/CSV/Reader.php
@@ -1,92 +1,52 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\CSV;
 
-use OpenSpout\Common\Exception\IOException;
-use OpenSpout\Common\Helper\GlobalFunctionsHelper;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Reader\Common\Creator\InternalEntityFactoryInterface;
-use OpenSpout\Reader\Common\Entity\Options;
-use OpenSpout\Reader\CSV\Creator\InternalEntityFactory;
-use OpenSpout\Reader\ReaderAbstract;
+use OpenSpout\Common\Helper\EncodingHelper;
+use OpenSpout\Reader\AbstractReader;
 
 /**
- * This class provides support to read data from a CSV file.
+ * @extends AbstractReader<SheetIterator>
  */
-class Reader extends ReaderAbstract
+final class Reader extends AbstractReader
 {
     /** @var resource Pointer to the file to be written */
-    protected $filePointer;
+    private $filePointer;
 
     /** @var SheetIterator To iterator over the CSV unique "sheet" */
-    protected $sheetIterator;
+    private SheetIterator $sheetIterator;
 
     /** @var string Original value for the "auto_detect_line_endings" INI value */
-    protected $originalAutoDetectLineEndings;
+    private string $originalAutoDetectLineEndings;
 
     /** @var bool Whether the code is running with PHP >= 8.1 */
-    private $isRunningAtLeastPhp81;
+    private bool $isRunningAtLeastPhp81;
+
+    private Options $options;
+    private EncodingHelper $encodingHelper;
 
     public function __construct(
-        OptionsManagerInterface $optionsManager,
-        GlobalFunctionsHelper $globalFunctionsHelper,
-        InternalEntityFactoryInterface $entityFactory
+        ?Options $options = null,
+        ?EncodingHelper $encodingHelper = null
     ) {
-        parent::__construct($optionsManager, $globalFunctionsHelper, $entityFactory);
-        $this->isRunningAtLeastPhp81 = version_compare(PHP_VERSION, '8.1.0') >= 0;
+        $this->options = $options ?? new Options();
+        $this->encodingHelper = $encodingHelper ?? EncodingHelper::factory();
+        $this->isRunningAtLeastPhp81 = \PHP_VERSION_ID >= 80100;
     }
 
-    /**
-     * Sets the field delimiter for the CSV.
-     * Needs to be called before opening the reader.
-     *
-     * @param string $fieldDelimiter Character that delimits fields
-     *
-     * @return Reader
-     */
-    public function setFieldDelimiter($fieldDelimiter)
+    public function getSheetIterator(): SheetIterator
     {
-        $this->optionsManager->setOption(Options::FIELD_DELIMITER, $fieldDelimiter);
+        $this->ensureStreamOpened();
 
-        return $this;
-    }
-
-    /**
-     * Sets the field enclosure for the CSV.
-     * Needs to be called before opening the reader.
-     *
-     * @param string $fieldEnclosure Character that enclose fields
-     *
-     * @return Reader
-     */
-    public function setFieldEnclosure($fieldEnclosure)
-    {
-        $this->optionsManager->setOption(Options::FIELD_ENCLOSURE, $fieldEnclosure);
-
-        return $this;
-    }
-
-    /**
-     * Sets the encoding of the CSV file to be read.
-     * Needs to be called before opening the reader.
-     *
-     * @param string $encoding Encoding of the CSV file to be read
-     *
-     * @return Reader
-     */
-    public function setEncoding($encoding)
-    {
-        $this->optionsManager->setOption(Options::ENCODING, $encoding);
-
-        return $this;
+        return $this->sheetIterator;
     }
 
     /**
      * Returns whether stream wrappers are supported.
-     *
-     * @return bool
      */
-    protected function doesSupportStreamWrapper()
+    protected function doesSupportStreamWrapper(): bool
     {
         return true;
     }
@@ -99,51 +59,45 @@ class Reader extends ReaderAbstract
      *
      * @throws \OpenSpout\Common\Exception\IOException
      */
-    protected function openReader($filePath)
+    protected function openReader(string $filePath): void
     {
         // "auto_detect_line_endings" is deprecated in PHP 8.1
         if (!$this->isRunningAtLeastPhp81) {
-            $this->originalAutoDetectLineEndings = ini_get('auto_detect_line_endings');
+            // @codeCoverageIgnoreStart
+            $originalAutoDetectLineEndings = \ini_get('auto_detect_line_endings');
+            \assert(false !== $originalAutoDetectLineEndings);
+            $this->originalAutoDetectLineEndings = $originalAutoDetectLineEndings;
             ini_set('auto_detect_line_endings', '1');
+            // @codeCoverageIgnoreEnd
         }
 
-        $this->filePointer = $this->globalFunctionsHelper->fopen($filePath, 'r');
-        if (!$this->filePointer) {
-            throw new IOException("Could not open file {$filePath} for reading.");
-        }
+        $resource = fopen($filePath, 'r');
+        \assert(false !== $resource);
+        $this->filePointer = $resource;
 
-        /** @var InternalEntityFactory $entityFactory */
-        $entityFactory = $this->entityFactory;
-
-        $this->sheetIterator = $entityFactory->createSheetIterator(
-            $this->filePointer,
-            $this->optionsManager,
-            $this->globalFunctionsHelper
+        $this->sheetIterator = new SheetIterator(
+            new Sheet(
+                new RowIterator(
+                    $this->filePointer,
+                    $this->options,
+                    $this->encodingHelper
+                )
+            )
         );
     }
 
-    /**
-     * Returns an iterator to iterate over sheets.
-     *
-     * @return SheetIterator To iterate over sheets
-     */
-    protected function getConcreteSheetIterator()
-    {
-        return $this->sheetIterator;
-    }
-
     /**
      * Closes the reader. To be used after reading the file.
      */
-    protected function closeReader()
+    protected function closeReader(): void
     {
-        if (\is_resource($this->filePointer)) {
-            $this->globalFunctionsHelper->fclose($this->filePointer);
-        }
+        fclose($this->filePointer);
 
         // "auto_detect_line_endings" is deprecated in PHP 8.1
         if (!$this->isRunningAtLeastPhp81) {
+            // @codeCoverageIgnoreStart
             ini_set('auto_detect_line_endings', $this->originalAutoDetectLineEndings);
+            // @codeCoverageIgnoreEnd
         }
     }
 }
diff --git a/lib/openspout/src/Reader/CSV/RowIterator.php b/lib/openspout/src/Reader/CSV/RowIterator.php
index 497d26637ae..024711b8e1b 100644
--- a/lib/openspout/src/Reader/CSV/RowIterator.php
+++ b/lib/openspout/src/Reader/CSV/RowIterator.php
@@ -1,76 +1,52 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\CSV;
 
+use OpenSpout\Common\Entity\Cell;
 use OpenSpout\Common\Entity\Row;
 use OpenSpout\Common\Helper\EncodingHelper;
-use OpenSpout\Common\Helper\GlobalFunctionsHelper;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Reader\Common\Entity\Options;
-use OpenSpout\Reader\CSV\Creator\InternalEntityFactory;
 use OpenSpout\Reader\RowIteratorInterface;
 
 /**
  * Iterate over CSV rows.
  */
-class RowIterator implements RowIteratorInterface
+final class RowIterator implements RowIteratorInterface
 {
     /**
-     * Value passed to fgetcsv. 0 means "unlimited" (slightly slower but accomodates for very long lines).
+     * Value passed to fgetcsv. 0 means "unlimited" (slightly slower but accommodates for very long lines).
      */
     public const MAX_READ_BYTES_PER_LINE = 0;
 
     /** @var null|resource Pointer to the CSV file to read */
-    protected $filePointer;
+    private $filePointer;
 
     /** @var int Number of read rows */
-    protected $numReadRows = 0;
+    private int $numReadRows = 0;
 
     /** @var null|Row Buffer used to store the current row, while checking if there are more rows to read */
-    protected $rowBuffer;
+    private ?Row $rowBuffer;
 
     /** @var bool Indicates whether all rows have been read */
-    protected $hasReachedEndOfFile = false;
+    private bool $hasReachedEndOfFile = false;
 
-    /** @var string Defines the character used to delimit fields (one character only) */
-    protected $fieldDelimiter;
+    private Options $options;
 
-    /** @var string Defines the character used to enclose fields (one character only) */
-    protected $fieldEnclosure;
-
-    /** @var string Encoding of the CSV file to be read */
-    protected $encoding;
-
-    /** @var bool Whether empty rows should be returned or skipped */
-    protected $shouldPreserveEmptyRows;
-
-    /** @var \OpenSpout\Common\Helper\EncodingHelper Helper to work with different encodings */
-    protected $encodingHelper;
-
-    /** @var \OpenSpout\Reader\CSV\Creator\InternalEntityFactory Factory to create entities */
-    protected $entityFactory;
-
-    /** @var \OpenSpout\Common\Helper\GlobalFunctionsHelper Helper to work with global functions */
-    protected $globalFunctionsHelper;
+    /** @var EncodingHelper Helper to work with different encodings */
+    private EncodingHelper $encodingHelper;
 
     /**
      * @param resource $filePointer Pointer to the CSV file to read
      */
     public function __construct(
         $filePointer,
-        OptionsManagerInterface $optionsManager,
-        EncodingHelper $encodingHelper,
-        InternalEntityFactory $entityFactory,
-        GlobalFunctionsHelper $globalFunctionsHelper
+        Options $options,
+        EncodingHelper $encodingHelper
     ) {
         $this->filePointer = $filePointer;
-        $this->fieldDelimiter = $optionsManager->getOption(Options::FIELD_DELIMITER);
-        $this->fieldEnclosure = $optionsManager->getOption(Options::FIELD_ENCLOSURE);
-        $this->encoding = $optionsManager->getOption(Options::ENCODING);
-        $this->shouldPreserveEmptyRows = $optionsManager->getOption(Options::SHOULD_PRESERVE_EMPTY_ROWS);
+        $this->options = $options;
         $this->encodingHelper = $encodingHelper;
-        $this->entityFactory = $entityFactory;
-        $this->globalFunctionsHelper = $globalFunctionsHelper;
     }
 
     /**
@@ -78,7 +54,6 @@ class RowIterator implements RowIteratorInterface
      *
      * @see http://php.net/manual/en/iterator.rewind.php
      */
-    #[\ReturnTypeWillChange]
     public function rewind(): void
     {
         $this->rewindAndSkipBom();
@@ -94,10 +69,9 @@ class RowIterator implements RowIteratorInterface
      *
      * @see http://php.net/manual/en/iterator.valid.php
      */
-    #[\ReturnTypeWillChange]
     public function valid(): bool
     {
-        return $this->filePointer && !$this->hasReachedEndOfFile;
+        return null !== $this->filePointer && !$this->hasReachedEndOfFile;
     }
 
     /**
@@ -107,10 +81,9 @@ class RowIterator implements RowIteratorInterface
      *
      * @throws \OpenSpout\Common\Exception\EncodingConversionException If unable to convert data to UTF-8
      */
-    #[\ReturnTypeWillChange]
     public function next(): void
     {
-        $this->hasReachedEndOfFile = $this->globalFunctionsHelper->feof($this->filePointer);
+        $this->hasReachedEndOfFile = feof($this->filePointer);
 
         if (!$this->hasReachedEndOfFile) {
             $this->readDataForNextRow();
@@ -122,7 +95,6 @@ class RowIterator implements RowIteratorInterface
      *
      * @see http://php.net/manual/en/iterator.current.php
      */
-    #[\ReturnTypeWillChange]
     public function current(): ?Row
     {
         return $this->rowBuffer;
@@ -133,37 +105,27 @@ class RowIterator implements RowIteratorInterface
      *
      * @see http://php.net/manual/en/iterator.key.php
      */
-    #[\ReturnTypeWillChange]
     public function key(): int
     {
         return $this->numReadRows;
     }
 
-    /**
-     * Cleans up what was created to iterate over the object.
-     */
-    #[\ReturnTypeWillChange]
-    public function end(): void
-    {
-        // do nothing
-    }
-
     /**
      * This rewinds and skips the BOM if inserted at the beginning of the file
      * by moving the file pointer after it, so that it is not read.
      */
-    protected function rewindAndSkipBom()
+    private function rewindAndSkipBom(): void
     {
-        $byteOffsetToSkipBom = $this->encodingHelper->getBytesOffsetToSkipBOM($this->filePointer, $this->encoding);
+        $byteOffsetToSkipBom = $this->encodingHelper->getBytesOffsetToSkipBOM($this->filePointer, $this->options->ENCODING);
 
         // sets the cursor after the BOM (0 means no BOM, so rewind it)
-        $this->globalFunctionsHelper->fseek($this->filePointer, $byteOffsetToSkipBom);
+        fseek($this->filePointer, $byteOffsetToSkipBom);
     }
 
     /**
      * @throws \OpenSpout\Common\Exception\EncodingConversionException If unable to convert data to UTF-8
      */
-    protected function readDataForNextRow()
+    private function readDataForNextRow(): void
     {
         do {
             $rowData = $this->getNextUTF8EncodedRow();
@@ -171,8 +133,10 @@ class RowIterator implements RowIteratorInterface
 
         if (false !== $rowData) {
             // array_map will replace NULL values by empty strings
-            $rowDataBufferAsArray = array_map(function ($value) { return (string) $value; }, $rowData);
-            $this->rowBuffer = $this->entityFactory->createRowFromArray($rowDataBufferAsArray);
+            $rowDataBufferAsArray = array_map('\\strval', $rowData);
+            $this->rowBuffer = new Row(array_map(static function ($cellValue) {
+                return Cell::fromValue($cellValue);
+            }, $rowDataBufferAsArray), null);
             ++$this->numReadRows;
         } else {
             // If we reach this point, it means end of file was reached.
@@ -182,19 +146,19 @@ class RowIterator implements RowIteratorInterface
     }
 
     /**
-     * @param array|bool $currentRowData
+     * @param array<int, null|string>|bool $currentRowData
      *
      * @return bool Whether the data for the current row can be returned or if we need to keep reading
      */
-    protected function shouldReadNextRow($currentRowData)
+    private function shouldReadNextRow($currentRowData): bool
     {
         $hasSuccessfullyFetchedRowData = (false !== $currentRowData);
-        $hasNowReachedEndOfFile = $this->globalFunctionsHelper->feof($this->filePointer);
+        $hasNowReachedEndOfFile = feof($this->filePointer);
         $isEmptyLine = $this->isEmptyLine($currentRowData);
 
         return
             (!$hasSuccessfullyFetchedRowData && !$hasNowReachedEndOfFile)
-            || (!$this->shouldPreserveEmptyRows && $isEmptyLine)
+            || (!$this->options->SHOULD_PRESERVE_EMPTY_ROWS && $isEmptyLine)
         ;
     }
 
@@ -203,19 +167,25 @@ class RowIterator implements RowIteratorInterface
      * As fgetcsv() does not manage correctly encoding for non UTF-8 data,
      * we remove manually whitespace with ltrim or rtrim (depending on the order of the bytes).
      *
-     * @throws \OpenSpout\Common\Exception\EncodingConversionException If unable to convert data to UTF-8
+     * @return array<int, null|string>|false The row for the current file pointer, encoded in UTF-8 or FALSE if nothing to read
      *
-     * @return array|false The row for the current file pointer, encoded in UTF-8 or FALSE if nothing to read
+     * @throws \OpenSpout\Common\Exception\EncodingConversionException If unable to convert data to UTF-8
      */
-    protected function getNextUTF8EncodedRow()
+    private function getNextUTF8EncodedRow(): array|false
     {
-        $encodedRowData = $this->globalFunctionsHelper->fgetcsv($this->filePointer, self::MAX_READ_BYTES_PER_LINE, $this->fieldDelimiter, $this->fieldEnclosure);
+        $encodedRowData = fgetcsv(
+            $this->filePointer,
+            self::MAX_READ_BYTES_PER_LINE,
+            $this->options->FIELD_DELIMITER,
+            $this->options->FIELD_ENCLOSURE,
+            ''
+        );
         if (false === $encodedRowData) {
             return false;
         }
 
         foreach ($encodedRowData as $cellIndex => $cellValue) {
-            switch ($this->encoding) {
+            switch ($this->options->ENCODING) {
                 case EncodingHelper::ENCODING_UTF16_LE:
                 case EncodingHelper::ENCODING_UTF32_LE:
                     // remove whitespace from the beginning of a string as fgetcsv() add extra whitespace when it try to explode non UTF-8 data
@@ -231,18 +201,18 @@ class RowIterator implements RowIteratorInterface
                     break;
             }
 
-            $encodedRowData[$cellIndex] = $this->encodingHelper->attemptConversionToUTF8($cellValue, $this->encoding);
+            $encodedRowData[$cellIndex] = $this->encodingHelper->attemptConversionToUTF8($cellValue, $this->options->ENCODING);
         }
 
         return $encodedRowData;
     }
 
     /**
-     * @param array|bool $lineData Array containing the cells value for the line
+     * @param array<int, null|string>|bool $lineData Array containing the cells value for the line
      *
      * @return bool Whether the given line is empty
      */
-    protected function isEmptyLine($lineData)
+    private function isEmptyLine($lineData): bool
     {
         return \is_array($lineData) && 1 === \count($lineData) && null === $lineData[0];
     }
diff --git a/lib/openspout/src/Reader/CSV/Sheet.php b/lib/openspout/src/Reader/CSV/Sheet.php
index f64b2ee6d86..f4e1be1c697 100644
--- a/lib/openspout/src/Reader/CSV/Sheet.php
+++ b/lib/openspout/src/Reader/CSV/Sheet.php
@@ -1,13 +1,18 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\CSV;
 
 use OpenSpout\Reader\SheetInterface;
 
-class Sheet implements SheetInterface
+/**
+ * @implements SheetInterface<RowIterator>
+ */
+final class Sheet implements SheetInterface
 {
-    /** @var \OpenSpout\Reader\CSV\RowIterator To iterate over the CSV's rows */
-    protected $rowIterator;
+    /** @var RowIterator To iterate over the CSV's rows */
+    private RowIterator $rowIterator;
 
     /**
      * @param RowIterator $rowIterator Corresponding row iterator
@@ -17,10 +22,7 @@ class Sheet implements SheetInterface
         $this->rowIterator = $rowIterator;
     }
 
-    /**
-     * @return \OpenSpout\Reader\CSV\RowIterator
-     */
-    public function getRowIterator()
+    public function getRowIterator(): RowIterator
     {
         return $this->rowIterator;
     }
@@ -28,7 +30,7 @@ class Sheet implements SheetInterface
     /**
      * @return int Index of the sheet
      */
-    public function getIndex()
+    public function getIndex(): int
     {
         return 0;
     }
@@ -36,7 +38,7 @@ class Sheet implements SheetInterface
     /**
      * @return string Name of the sheet - empty string since CSV does not support that
      */
-    public function getName()
+    public function getName(): string
     {
         return '';
     }
@@ -44,15 +46,7 @@ class Sheet implements SheetInterface
     /**
      * @return bool Always TRUE as there is only one sheet
      */
-    public function isActive()
-    {
-        return true;
-    }
-
-    /**
-     * @return bool Always TRUE as the only sheet is always visible
-     */
-    public function isVisible()
+    public function isActive(): bool
     {
         return true;
     }
diff --git a/lib/openspout/src/Reader/CSV/SheetIterator.php b/lib/openspout/src/Reader/CSV/SheetIterator.php
index cbcf7c12f64..7bba3aa09b6 100644
--- a/lib/openspout/src/Reader/CSV/SheetIterator.php
+++ b/lib/openspout/src/Reader/CSV/SheetIterator.php
@@ -1,24 +1,26 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\CSV;
 
 use OpenSpout\Reader\SheetIteratorInterface;
 
 /**
- * Iterate over CSV unique "sheet".
+ * @implements SheetIteratorInterface<Sheet>
  */
-class SheetIterator implements SheetIteratorInterface
+final class SheetIterator implements SheetIteratorInterface
 {
     /** @var Sheet The CSV unique "sheet" */
-    protected $sheet;
+    private Sheet $sheet;
 
     /** @var bool Whether the unique "sheet" has already been read */
-    protected $hasReadUniqueSheet = false;
+    private bool $hasReadUniqueSheet = false;
 
     /**
      * @param Sheet $sheet Corresponding unique sheet
      */
-    public function __construct($sheet)
+    public function __construct(Sheet $sheet)
     {
         $this->sheet = $sheet;
     }
@@ -28,7 +30,6 @@ class SheetIterator implements SheetIteratorInterface
      *
      * @see http://php.net/manual/en/iterator.rewind.php
      */
-    #[\ReturnTypeWillChange]
     public function rewind(): void
     {
         $this->hasReadUniqueSheet = false;
@@ -39,7 +40,6 @@ class SheetIterator implements SheetIteratorInterface
      *
      * @see http://php.net/manual/en/iterator.valid.php
      */
-    #[\ReturnTypeWillChange]
     public function valid(): bool
     {
         return !$this->hasReadUniqueSheet;
@@ -50,7 +50,6 @@ class SheetIterator implements SheetIteratorInterface
      *
      * @see http://php.net/manual/en/iterator.next.php
      */
-    #[\ReturnTypeWillChange]
     public function next(): void
     {
         $this->hasReadUniqueSheet = true;
@@ -61,7 +60,6 @@ class SheetIterator implements SheetIteratorInterface
      *
      * @see http://php.net/manual/en/iterator.current.php
      */
-    #[\ReturnTypeWillChange]
     public function current(): Sheet
     {
         return $this->sheet;
@@ -72,18 +70,8 @@ class SheetIterator implements SheetIteratorInterface
      *
      * @see http://php.net/manual/en/iterator.key.php
      */
-    #[\ReturnTypeWillChange]
     public function key(): int
     {
         return 1;
     }
-
-    /**
-     * Cleans up what was created to iterate over the object.
-     */
-    #[\ReturnTypeWillChange]
-    public function end(): void
-    {
-        // do nothing
-    }
 }
diff --git a/lib/openspout/src/Reader/Common/ColumnWidth.php b/lib/openspout/src/Reader/Common/ColumnWidth.php
new file mode 100644
index 00000000000..1350a10e2ea
--- /dev/null
+++ b/lib/openspout/src/Reader/Common/ColumnWidth.php
@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Reader\Common;
+
+/**
+ * @internal
+ */
+final class ColumnWidth
+{
+    /**
+     * @param positive-int $start
+     * @param positive-int $end
+     */
+    public function __construct(
+        public int $start,
+        public int $end,
+        public float $width,
+    ) {
+    }
+}
diff --git a/lib/openspout/src/Reader/Common/Creator/InternalEntityFactoryInterface.php b/lib/openspout/src/Reader/Common/Creator/InternalEntityFactoryInterface.php
deleted file mode 100644
index e9cee4fe6a9..00000000000
--- a/lib/openspout/src/Reader/Common/Creator/InternalEntityFactoryInterface.php
+++ /dev/null
@@ -1,26 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\Common\Creator;
-
-use OpenSpout\Common\Entity\Cell;
-use OpenSpout\Common\Entity\Row;
-
-/**
- * Interface EntityFactoryInterface.
- */
-interface InternalEntityFactoryInterface
-{
-    /**
-     * @param Cell[] $cells
-     *
-     * @return Row
-     */
-    public function createRow(array $cells = []);
-
-    /**
-     * @param mixed $cellValue
-     *
-     * @return Cell
-     */
-    public function createCell($cellValue);
-}
diff --git a/lib/openspout/src/Reader/Common/Creator/ReaderEntityFactory.php b/lib/openspout/src/Reader/Common/Creator/ReaderEntityFactory.php
deleted file mode 100644
index 324d4a437f9..00000000000
--- a/lib/openspout/src/Reader/Common/Creator/ReaderEntityFactory.php
+++ /dev/null
@@ -1,72 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\Common\Creator;
-
-use OpenSpout\Common\Exception\UnsupportedTypeException;
-use OpenSpout\Common\Type;
-use OpenSpout\Reader\ReaderInterface;
-
-/**
- * Factory to create external entities.
- */
-class ReaderEntityFactory
-{
-    /**
-     * Creates a reader by file extension.
-     *
-     * @param string $path The path to the spreadsheet file. Supported extensions are .csv, .ods and .xlsx
-     *
-     * @throws \OpenSpout\Common\Exception\UnsupportedTypeException
-     *
-     * @return ReaderInterface
-     */
-    public static function createReaderFromFile(string $path)
-    {
-        return ReaderFactory::createFromFile($path);
-    }
-
-    /**
-     * This creates an instance of a CSV reader.
-     *
-     * @return \OpenSpout\Reader\CSV\Reader
-     */
-    public static function createCSVReader()
-    {
-        try {
-            return ReaderFactory::createFromType(Type::CSV);
-        } catch (UnsupportedTypeException $e) {
-            // should never happen
-            return null;
-        }
-    }
-
-    /**
-     * This creates an instance of a XLSX reader.
-     *
-     * @return \OpenSpout\Reader\XLSX\Reader
-     */
-    public static function createXLSXReader()
-    {
-        try {
-            return ReaderFactory::createFromType(Type::XLSX);
-        } catch (UnsupportedTypeException $e) {
-            // should never happen
-            return null;
-        }
-    }
-
-    /**
-     * This creates an instance of a ODS reader.
-     *
-     * @return \OpenSpout\Reader\ODS\Reader
-     */
-    public static function createODSReader()
-    {
-        try {
-            return ReaderFactory::createFromType(Type::ODS);
-        } catch (UnsupportedTypeException $e) {
-            // should never happen
-            return null;
-        }
-    }
-}
diff --git a/lib/openspout/src/Reader/Common/Creator/ReaderFactory.php b/lib/openspout/src/Reader/Common/Creator/ReaderFactory.php
index 5c42701b501..c72bcfa4b91 100644
--- a/lib/openspout/src/Reader/Common/Creator/ReaderFactory.php
+++ b/lib/openspout/src/Reader/Common/Creator/ReaderFactory.php
@@ -1,31 +1,21 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Common\Creator;
 
-use OpenSpout\Common\Creator\HelperFactory;
+use OpenSpout\Common\Exception\IOException;
 use OpenSpout\Common\Exception\UnsupportedTypeException;
-use OpenSpout\Common\Type;
-use OpenSpout\Reader\CSV\Creator\InternalEntityFactory as CSVInternalEntityFactory;
-use OpenSpout\Reader\CSV\Manager\OptionsManager as CSVOptionsManager;
 use OpenSpout\Reader\CSV\Reader as CSVReader;
-use OpenSpout\Reader\ODS\Creator\HelperFactory as ODSHelperFactory;
-use OpenSpout\Reader\ODS\Creator\InternalEntityFactory as ODSInternalEntityFactory;
-use OpenSpout\Reader\ODS\Creator\ManagerFactory as ODSManagerFactory;
-use OpenSpout\Reader\ODS\Manager\OptionsManager as ODSOptionsManager;
 use OpenSpout\Reader\ODS\Reader as ODSReader;
 use OpenSpout\Reader\ReaderInterface;
-use OpenSpout\Reader\XLSX\Creator\HelperFactory as XLSXHelperFactory;
-use OpenSpout\Reader\XLSX\Creator\InternalEntityFactory as XLSXInternalEntityFactory;
-use OpenSpout\Reader\XLSX\Creator\ManagerFactory as XLSXManagerFactory;
-use OpenSpout\Reader\XLSX\Manager\OptionsManager as XLSXOptionsManager;
-use OpenSpout\Reader\XLSX\Manager\SharedStringsCaching\CachingStrategyFactory;
 use OpenSpout\Reader\XLSX\Reader as XLSXReader;
 
 /**
  * This factory is used to create readers, based on the type of the file to be read.
  * It supports CSV, XLSX and ODS formats.
  */
-class ReaderFactory
+final class ReaderFactory
 {
     /**
      * Creates a reader by file extension.
@@ -33,77 +23,40 @@ class ReaderFactory
      * @param string $path The path to the spreadsheet file. Supported extensions are .csv,.ods and .xlsx
      *
      * @throws \OpenSpout\Common\Exception\UnsupportedTypeException
-     *
-     * @return ReaderInterface
      */
-    public static function createFromFile(string $path)
+    public static function createFromFile(string $path): ReaderInterface
     {
         $extension = strtolower(pathinfo($path, PATHINFO_EXTENSION));
 
-        return self::createFromType($extension);
+        return match ($extension) {
+            'csv' => new CSVReader(),
+            'xlsx' => new XLSXReader(),
+            'ods' => new ODSReader(),
+            default => throw new UnsupportedTypeException('No readers supporting the given type: '.$extension),
+        };
     }
 
     /**
-     * This creates an instance of the appropriate reader, given the type of the file to be read.
+     * Creates a reader by mime type.
      *
-     * @param string $readerType Type of the reader to instantiate
+     * @param string $path the path to the spreadsheet file
      *
      * @throws \OpenSpout\Common\Exception\UnsupportedTypeException
-     *
-     * @return ReaderInterface
+     * @throws \OpenSpout\Common\Exception\IOException
      */
-    public static function createFromType($readerType)
+    public static function createFromFileByMimeType(string $path): ReaderInterface
     {
-        switch ($readerType) {
-            case Type::CSV: return self::createCSVReader();
-
-            case Type::XLSX: return self::createXLSXReader();
-
-            case Type::ODS: return self::createODSReader();
-
-            default:
-                throw new UnsupportedTypeException('No readers supporting the given type: '.$readerType);
+        if (!file_exists($path)) {
+            throw new IOException("Could not open {$path} for reading! File does not exist.");
         }
-    }
 
-    /**
-     * @return CSVReader
-     */
-    private static function createCSVReader()
-    {
-        $optionsManager = new CSVOptionsManager();
-        $helperFactory = new HelperFactory();
-        $entityFactory = new CSVInternalEntityFactory($helperFactory);
-        $globalFunctionsHelper = $helperFactory->createGlobalFunctionsHelper();
+        $mime_type = mime_content_type($path);
 
-        return new CSVReader($optionsManager, $globalFunctionsHelper, $entityFactory);
-    }
-
-    /**
-     * @return XLSXReader
-     */
-    private static function createXLSXReader()
-    {
-        $optionsManager = new XLSXOptionsManager();
-        $helperFactory = new XLSXHelperFactory();
-        $managerFactory = new XLSXManagerFactory($helperFactory, new CachingStrategyFactory());
-        $entityFactory = new XLSXInternalEntityFactory($managerFactory, $helperFactory);
-        $globalFunctionsHelper = $helperFactory->createGlobalFunctionsHelper();
-
-        return new XLSXReader($optionsManager, $globalFunctionsHelper, $entityFactory, $managerFactory);
-    }
-
-    /**
-     * @return ODSReader
-     */
-    private static function createODSReader()
-    {
-        $optionsManager = new ODSOptionsManager();
-        $helperFactory = new ODSHelperFactory();
-        $managerFactory = new ODSManagerFactory();
-        $entityFactory = new ODSInternalEntityFactory($helperFactory, $managerFactory);
-        $globalFunctionsHelper = $helperFactory->createGlobalFunctionsHelper();
-
-        return new ODSReader($optionsManager, $globalFunctionsHelper, $entityFactory);
+        return match ($mime_type) {
+            'application/csv', 'text/csv', 'text/plain' => new CSVReader(),
+            'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' => new XLSXReader(),
+            'application/vnd.oasis.opendocument.spreadsheet' => new ODSReader(),
+            default => throw new UnsupportedTypeException('No readers supporting the given type: '.$mime_type),
+        };
     }
 }
diff --git a/lib/openspout/src/Reader/Common/Entity/Options.php b/lib/openspout/src/Reader/Common/Entity/Options.php
deleted file mode 100644
index 48e15a1903d..00000000000
--- a/lib/openspout/src/Reader/Common/Entity/Options.php
+++ /dev/null
@@ -1,22 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\Common\Entity;
-
-/**
- * Readers' options holder.
- */
-abstract class Options
-{
-    // Common options
-    public const SHOULD_FORMAT_DATES = 'shouldFormatDates';
-    public const SHOULD_PRESERVE_EMPTY_ROWS = 'shouldPreserveEmptyRows';
-
-    // CSV specific options
-    public const FIELD_DELIMITER = 'fieldDelimiter';
-    public const FIELD_ENCLOSURE = 'fieldEnclosure';
-    public const ENCODING = 'encoding';
-
-    // XLSX specific options
-    public const TEMP_FOLDER = 'tempFolder';
-    public const SHOULD_USE_1904_DATES = 'shouldUse1904Dates';
-}
diff --git a/lib/openspout/src/Reader/Common/Manager/RowManager.php b/lib/openspout/src/Reader/Common/Manager/RowManager.php
index cd57337a310..a4f808096b2 100644
--- a/lib/openspout/src/Reader/Common/Manager/RowManager.php
+++ b/lib/openspout/src/Reader/Common/Manager/RowManager.php
@@ -1,51 +1,26 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Common\Manager;
 
+use OpenSpout\Common\Entity\Cell;
 use OpenSpout\Common\Entity\Row;
-use OpenSpout\Reader\Common\Creator\InternalEntityFactoryInterface;
 
-class RowManager
+/**
+ * @internal
+ */
+final class RowManager
 {
-    /** @var InternalEntityFactoryInterface Factory to create entities */
-    private $entityFactory;
-
-    /**
-     * @param InternalEntityFactoryInterface $entityFactory Factory to create entities
-     */
-    public function __construct(InternalEntityFactoryInterface $entityFactory)
-    {
-        $this->entityFactory = $entityFactory;
-    }
-
-    /**
-     * Detect whether a row is considered empty.
-     * An empty row has all of its cells empty.
-     *
-     * @return bool
-     */
-    public function isEmpty(Row $row)
-    {
-        foreach ($row->getCells() as $cell) {
-            if (!$cell->isEmpty()) {
-                return false;
-            }
-        }
-
-        return true;
-    }
-
     /**
      * Fills the missing indexes of a row with empty cells.
-     *
-     * @return Row
      */
-    public function fillMissingIndexesWithEmptyCells(Row $row)
+    public function fillMissingIndexesWithEmptyCells(Row $row): void
     {
         $numCells = $row->getNumCells();
 
         if (0 === $numCells) {
-            return $row;
+            return;
         }
 
         $rowCells = $row->getCells();
@@ -62,7 +37,7 @@ class RowManager
 
         for ($cellIndex = 0; $cellIndex < $maxCellIndex; ++$cellIndex) {
             if (!isset($rowCells[$cellIndex])) {
-                $row->setCellAtIndex($this->entityFactory->createCell(''), $cellIndex);
+                $row->setCellAtIndex(Cell::fromValue(''), $cellIndex);
                 $needsSorting = true;
             }
         }
@@ -72,7 +47,5 @@ class RowManager
             ksort($rowCells);
             $row->setCells($rowCells);
         }
-
-        return $row;
     }
 }
diff --git a/lib/openspout/src/Reader/Common/XMLProcessor.php b/lib/openspout/src/Reader/Common/XMLProcessor.php
index 967c0ffc6da..85dff666eba 100644
--- a/lib/openspout/src/Reader/Common/XMLProcessor.php
+++ b/lib/openspout/src/Reader/Common/XMLProcessor.php
@@ -1,13 +1,16 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Common;
 
 use OpenSpout\Reader\Wrapper\XMLReader;
+use ReflectionMethod;
 
 /**
- * Helps process XML files.
+ * @internal
  */
-class XMLProcessor
+final class XMLProcessor
 {
     // Node types
     public const NODE_TYPE_START = XMLReader::ELEMENT;
@@ -21,16 +24,16 @@ class XMLProcessor
     public const PROCESSING_CONTINUE = 1;
     public const PROCESSING_STOP = 2;
 
-    /** @var \OpenSpout\Reader\Wrapper\XMLReader The XMLReader object that will help read sheet's XML data */
-    protected $xmlReader;
+    /** @var XMLReader The XMLReader object that will help read sheet's XML data */
+    private XMLReader $xmlReader;
 
-    /** @var array Registered callbacks */
-    private $callbacks = [];
+    /** @var array<string, array{reflectionMethod: ReflectionMethod, reflectionObject: object}> Registered callbacks */
+    private array $callbacks = [];
 
     /**
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XMLReader object
+     * @param XMLReader $xmlReader XMLReader object
      */
-    public function __construct($xmlReader)
+    public function __construct(XMLReader $xmlReader)
     {
         $this->xmlReader = $xmlReader;
     }
@@ -39,10 +42,8 @@ class XMLProcessor
      * @param string   $nodeName A callback may be triggered when a node with this name is read
      * @param int      $nodeType Type of the node [NODE_TYPE_START || NODE_TYPE_END]
      * @param callable $callback Callback to execute when the read node has the given name and type
-     *
-     * @return XMLProcessor
      */
-    public function registerCallback($nodeName, $nodeType, $callback)
+    public function registerCallback(string $nodeName, int $nodeType, $callback): self
     {
         $callbackKey = $this->getCallbackKey($nodeName, $nodeType);
         $this->callbacks[$callbackKey] = $this->getInvokableCallbackData($callback);
@@ -56,7 +57,7 @@ class XMLProcessor
      *
      * @throws \OpenSpout\Reader\Exception\XMLProcessingException
      */
-    public function readUntilStopped()
+    public function readUntilStopped(): void
     {
         while ($this->xmlReader->read()) {
             $nodeType = $this->xmlReader->nodeType;
@@ -82,7 +83,7 @@ class XMLProcessor
      *
      * @return string Key used to store the associated callback
      */
-    private function getCallbackKey($nodeName, $nodeType)
+    private function getCallbackKey(string $nodeName, int $nodeType): string
     {
         return "{$nodeName}{$nodeType}";
     }
@@ -95,13 +96,13 @@ class XMLProcessor
      *
      * @param callable $callback Array reference to a callback: [OBJECT, METHOD_NAME]
      *
-     * @return array Associative array containing the elements needed to invoke the callback using Reflection
+     * @return array{reflectionMethod: ReflectionMethod, reflectionObject: object} Associative array containing the elements needed to invoke the callback using Reflection
      */
-    private function getInvokableCallbackData($callback)
+    private function getInvokableCallbackData($callback): array
     {
         $callbackObject = $callback[0];
         $callbackMethodName = $callback[1];
-        $reflectionMethod = new \ReflectionMethod(\get_class($callbackObject), $callbackMethodName);
+        $reflectionMethod = new ReflectionMethod($callbackObject, $callbackMethodName);
         $reflectionMethod->setAccessible(true);
 
         return [
@@ -115,9 +116,9 @@ class XMLProcessor
      * @param string $nodeNameWithoutPrefix      Name of the same node, un-prefixed
      * @param int    $nodeType                   Type of the node [NODE_TYPE_START || NODE_TYPE_END]
      *
-     * @return null|array Callback data to be used for execution when a node of the given name/type is read or NULL if none found
+     * @return null|array{reflectionMethod: ReflectionMethod, reflectionObject: object} Callback data to be used for execution when a node of the given name/type is read or NULL if none found
      */
-    private function getRegisteredCallbackData($nodeNamePossiblyWithPrefix, $nodeNameWithoutPrefix, $nodeType)
+    private function getRegisteredCallbackData(string $nodeNamePossiblyWithPrefix, string $nodeNameWithoutPrefix, int $nodeType): ?array
     {
         // With prefixed nodes, we should match if (by order of preference):
         //  1. the callback was registered with the prefixed node name (e.g. "x:worksheet")
@@ -136,12 +137,12 @@ class XMLProcessor
     }
 
     /**
-     * @param array $callbackData Associative array containing data to invoke the callback using Reflection
-     * @param array $args         Arguments to pass to the callback
+     * @param array{reflectionMethod: ReflectionMethod, reflectionObject: object} $callbackData Associative array containing data to invoke the callback using Reflection
+     * @param XMLReader[]                                                         $args         Arguments to pass to the callback
      *
      * @return int Callback response
      */
-    private function invokeCallback($callbackData, $args)
+    private function invokeCallback(array $callbackData, array $args): int
     {
         $reflectionMethod = $callbackData[self::CALLBACK_REFLECTION_METHOD];
         $callbackObject = $callbackData[self::CALLBACK_REFLECTION_OBJECT];
diff --git a/lib/openspout/src/Reader/Exception/InvalidValueException.php b/lib/openspout/src/Reader/Exception/InvalidValueException.php
index 9bbcebdf03b..3f5c4b04215 100644
--- a/lib/openspout/src/Reader/Exception/InvalidValueException.php
+++ b/lib/openspout/src/Reader/Exception/InvalidValueException.php
@@ -1,29 +1,22 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Exception;
 
 use Throwable;
 
-class InvalidValueException extends ReaderException
+final class InvalidValueException extends ReaderException
 {
-    /** @var mixed */
-    private $invalidValue;
+    private string $invalidValue;
 
-    /**
-     * @param mixed  $invalidValue
-     * @param string $message
-     * @param int    $code
-     */
-    public function __construct($invalidValue, $message = '', $code = 0, Throwable $previous = null)
+    public function __construct(string $invalidValue, string $message = '', int $code = 0, ?Throwable $previous = null)
     {
         $this->invalidValue = $invalidValue;
         parent::__construct($message, $code, $previous);
     }
 
-    /**
-     * @return mixed
-     */
-    public function getInvalidValue()
+    public function getInvalidValue(): string
     {
         return $this->invalidValue;
     }
diff --git a/lib/openspout/src/Reader/Exception/IteratorNotRewindableException.php b/lib/openspout/src/Reader/Exception/IteratorNotRewindableException.php
index 06aac22621c..80bff913fbd 100644
--- a/lib/openspout/src/Reader/Exception/IteratorNotRewindableException.php
+++ b/lib/openspout/src/Reader/Exception/IteratorNotRewindableException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Exception;
 
-class IteratorNotRewindableException extends ReaderException
+final class IteratorNotRewindableException extends ReaderException
 {
 }
diff --git a/lib/openspout/src/Reader/Exception/NoSheetsFoundException.php b/lib/openspout/src/Reader/Exception/NoSheetsFoundException.php
index e02b974efda..b240b3dee73 100644
--- a/lib/openspout/src/Reader/Exception/NoSheetsFoundException.php
+++ b/lib/openspout/src/Reader/Exception/NoSheetsFoundException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Exception;
 
-class NoSheetsFoundException extends ReaderException
+final class NoSheetsFoundException extends ReaderException
 {
 }
diff --git a/lib/openspout/src/Reader/Exception/ReaderException.php b/lib/openspout/src/Reader/Exception/ReaderException.php
index 8ff797e52cd..676158904c9 100644
--- a/lib/openspout/src/Reader/Exception/ReaderException.php
+++ b/lib/openspout/src/Reader/Exception/ReaderException.php
@@ -1,9 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Exception;
 
-use OpenSpout\Common\Exception\SpoutException;
+use OpenSpout\Common\Exception\OpenSpoutException;
 
-abstract class ReaderException extends SpoutException
+abstract class ReaderException extends OpenSpoutException
 {
 }
diff --git a/lib/openspout/src/Reader/Exception/ReaderNotOpenedException.php b/lib/openspout/src/Reader/Exception/ReaderNotOpenedException.php
index 16c01352e2a..913cb21aeb9 100644
--- a/lib/openspout/src/Reader/Exception/ReaderNotOpenedException.php
+++ b/lib/openspout/src/Reader/Exception/ReaderNotOpenedException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Exception;
 
-class ReaderNotOpenedException extends ReaderException
+final class ReaderNotOpenedException extends ReaderException
 {
 }
diff --git a/lib/openspout/src/Reader/Exception/SharedStringNotFoundException.php b/lib/openspout/src/Reader/Exception/SharedStringNotFoundException.php
index 088f446120d..0f50ac69ffa 100644
--- a/lib/openspout/src/Reader/Exception/SharedStringNotFoundException.php
+++ b/lib/openspout/src/Reader/Exception/SharedStringNotFoundException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Exception;
 
-class SharedStringNotFoundException extends ReaderException
+final class SharedStringNotFoundException extends ReaderException
 {
 }
diff --git a/lib/openspout/src/Reader/Exception/XMLProcessingException.php b/lib/openspout/src/Reader/Exception/XMLProcessingException.php
index 7e4c5782b78..bd7d1b9ea76 100644
--- a/lib/openspout/src/Reader/Exception/XMLProcessingException.php
+++ b/lib/openspout/src/Reader/Exception/XMLProcessingException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Exception;
 
-class XMLProcessingException extends ReaderException
+final class XMLProcessingException extends ReaderException
 {
 }
diff --git a/lib/openspout/src/Reader/IteratorInterface.php b/lib/openspout/src/Reader/IteratorInterface.php
deleted file mode 100644
index 6e14b6d839d..00000000000
--- a/lib/openspout/src/Reader/IteratorInterface.php
+++ /dev/null
@@ -1,14 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader;
-
-/**
- * Interface IteratorInterface.
- */
-interface IteratorInterface extends \Iterator
-{
-    /**
-     * Cleans up what was created to iterate over the object.
-     */
-    public function end();
-}
diff --git a/lib/openspout/src/Reader/ODS/Creator/HelperFactory.php b/lib/openspout/src/Reader/ODS/Creator/HelperFactory.php
deleted file mode 100644
index eb5ba738382..00000000000
--- a/lib/openspout/src/Reader/ODS/Creator/HelperFactory.php
+++ /dev/null
@@ -1,43 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\ODS\Creator;
-
-use OpenSpout\Reader\ODS\Helper\CellValueFormatter;
-use OpenSpout\Reader\ODS\Helper\SettingsHelper;
-
-/**
- * Factory to create helpers.
- */
-class HelperFactory extends \OpenSpout\Common\Creator\HelperFactory
-{
-    /**
-     * @param bool $shouldFormatDates Whether date/time values should be returned as PHP objects or be formatted as strings
-     *
-     * @return CellValueFormatter
-     */
-    public function createCellValueFormatter($shouldFormatDates)
-    {
-        $escaper = $this->createStringsEscaper();
-
-        return new CellValueFormatter($shouldFormatDates, $escaper);
-    }
-
-    /**
-     * @param InternalEntityFactory $entityFactory
-     *
-     * @return SettingsHelper
-     */
-    public function createSettingsHelper($entityFactory)
-    {
-        return new SettingsHelper($entityFactory);
-    }
-
-    /**
-     * @return \OpenSpout\Common\Helper\Escaper\ODS
-     */
-    public function createStringsEscaper()
-    {
-        // @noinspection PhpUnnecessaryFullyQualifiedNameInspection
-        return new \OpenSpout\Common\Helper\Escaper\ODS();
-    }
-}
diff --git a/lib/openspout/src/Reader/ODS/Creator/InternalEntityFactory.php b/lib/openspout/src/Reader/ODS/Creator/InternalEntityFactory.php
deleted file mode 100644
index 960fec9e207..00000000000
--- a/lib/openspout/src/Reader/ODS/Creator/InternalEntityFactory.php
+++ /dev/null
@@ -1,124 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\ODS\Creator;
-
-use OpenSpout\Common\Entity\Cell;
-use OpenSpout\Common\Entity\Row;
-use OpenSpout\Reader\Common\Creator\InternalEntityFactoryInterface;
-use OpenSpout\Reader\Common\Entity\Options;
-use OpenSpout\Reader\Common\XMLProcessor;
-use OpenSpout\Reader\ODS\RowIterator;
-use OpenSpout\Reader\ODS\Sheet;
-use OpenSpout\Reader\ODS\SheetIterator;
-use OpenSpout\Reader\Wrapper\XMLReader;
-
-/**
- * Factory to create entities.
- */
-class InternalEntityFactory implements InternalEntityFactoryInterface
-{
-    /** @var HelperFactory */
-    private $helperFactory;
-
-    /** @var ManagerFactory */
-    private $managerFactory;
-
-    public function __construct(HelperFactory $helperFactory, ManagerFactory $managerFactory)
-    {
-        $this->helperFactory = $helperFactory;
-        $this->managerFactory = $managerFactory;
-    }
-
-    /**
-     * @param string                                            $filePath       Path of the file to be read
-     * @param \OpenSpout\Common\Manager\OptionsManagerInterface $optionsManager Reader's options manager
-     *
-     * @return SheetIterator
-     */
-    public function createSheetIterator($filePath, $optionsManager)
-    {
-        $escaper = $this->helperFactory->createStringsEscaper();
-        $settingsHelper = $this->helperFactory->createSettingsHelper($this);
-
-        return new SheetIterator($filePath, $optionsManager, $escaper, $settingsHelper, $this);
-    }
-
-    /**
-     * @param XMLReader                                         $xmlReader      XML Reader
-     * @param int                                               $sheetIndex     Index of the sheet, based on order in the workbook (zero-based)
-     * @param string                                            $sheetName      Name of the sheet
-     * @param bool                                              $isSheetActive  Whether the sheet was defined as active
-     * @param bool                                              $isSheetVisible Whether the sheet is visible
-     * @param \OpenSpout\Common\Manager\OptionsManagerInterface $optionsManager Reader's options manager
-     *
-     * @return Sheet
-     */
-    public function createSheet($xmlReader, $sheetIndex, $sheetName, $isSheetActive, $isSheetVisible, $optionsManager)
-    {
-        $rowIterator = $this->createRowIterator($xmlReader, $optionsManager);
-
-        return new Sheet($rowIterator, $sheetIndex, $sheetName, $isSheetActive, $isSheetVisible);
-    }
-
-    /**
-     * @param Cell[] $cells
-     *
-     * @return Row
-     */
-    public function createRow(array $cells = [])
-    {
-        return new Row($cells, null);
-    }
-
-    /**
-     * @param mixed $cellValue
-     *
-     * @return Cell
-     */
-    public function createCell($cellValue)
-    {
-        return new Cell($cellValue);
-    }
-
-    /**
-     * @return XMLReader
-     */
-    public function createXMLReader()
-    {
-        return new XMLReader();
-    }
-
-    /**
-     * @return \ZipArchive
-     */
-    public function createZipArchive()
-    {
-        return new \ZipArchive();
-    }
-
-    /**
-     * @param XMLReader                                         $xmlReader      XML Reader
-     * @param \OpenSpout\Common\Manager\OptionsManagerInterface $optionsManager Reader's options manager
-     *
-     * @return RowIterator
-     */
-    private function createRowIterator($xmlReader, $optionsManager)
-    {
-        $shouldFormatDates = $optionsManager->getOption(Options::SHOULD_FORMAT_DATES);
-        $cellValueFormatter = $this->helperFactory->createCellValueFormatter($shouldFormatDates);
-        $xmlProcessor = $this->createXMLProcessor($xmlReader);
-        $rowManager = $this->managerFactory->createRowManager($this);
-
-        return new RowIterator($xmlReader, $optionsManager, $cellValueFormatter, $xmlProcessor, $rowManager, $this);
-    }
-
-    /**
-     * @param XMLReader $xmlReader
-     *
-     * @return XMLProcessor
-     */
-    private function createXMLProcessor($xmlReader)
-    {
-        return new XMLProcessor($xmlReader);
-    }
-}
diff --git a/lib/openspout/src/Reader/ODS/Creator/ManagerFactory.php b/lib/openspout/src/Reader/ODS/Creator/ManagerFactory.php
deleted file mode 100644
index 546069e0fe8..00000000000
--- a/lib/openspout/src/Reader/ODS/Creator/ManagerFactory.php
+++ /dev/null
@@ -1,21 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\ODS\Creator;
-
-use OpenSpout\Reader\Common\Manager\RowManager;
-
-/**
- * Factory to create managers.
- */
-class ManagerFactory
-{
-    /**
-     * @param InternalEntityFactory $entityFactory Factory to create entities
-     *
-     * @return RowManager
-     */
-    public function createRowManager($entityFactory)
-    {
-        return new RowManager($entityFactory);
-    }
-}
diff --git a/lib/openspout/src/Reader/ODS/Helper/CellValueFormatter.php b/lib/openspout/src/Reader/ODS/Helper/CellValueFormatter.php
index 8e92b9ada30..3202e6e2c7b 100644
--- a/lib/openspout/src/Reader/ODS/Helper/CellValueFormatter.php
+++ b/lib/openspout/src/Reader/ODS/Helper/CellValueFormatter.php
@@ -1,15 +1,26 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\ODS\Helper;
 
+use DateInterval;
+use DateTimeImmutable;
+use DOMElement;
+use DOMNode;
+use DOMText;
+use Exception;
+use OpenSpout\Common\Helper\Escaper\ODS;
 use OpenSpout\Reader\Exception\InvalidValueException;
 
 /**
- * This class provides helper functions to format cell values.
+ * @internal
  */
-class CellValueFormatter
+final class CellValueFormatter
 {
-    /** Definition of all possible cell types */
+    /**
+     * Definition of all possible cell types.
+     */
     public const CELL_TYPE_STRING = 'string';
     public const CELL_TYPE_FLOAT = 'float';
     public const CELL_TYPE_BOOLEAN = 'boolean';
@@ -19,7 +30,9 @@ class CellValueFormatter
     public const CELL_TYPE_PERCENTAGE = 'percentage';
     public const CELL_TYPE_VOID = 'void';
 
-    /** Definition of XML nodes names used to parse data */
+    /**
+     * Definition of XML nodes names used to parse data.
+     */
     public const XML_NODE_P = 'p';
     public const XML_NODE_TEXT_A = 'text:a';
     public const XML_NODE_TEXT_SPAN = 'text:span';
@@ -27,7 +40,9 @@ class CellValueFormatter
     public const XML_NODE_TEXT_TAB = 'text:tab';
     public const XML_NODE_TEXT_LINE_BREAK = 'text:line-break';
 
-    /** Definition of XML attributes used to parse data */
+    /**
+     * Definition of XML attributes used to parse data.
+     */
     public const XML_ATTRIBUTE_TYPE = 'office:value-type';
     public const XML_ATTRIBUTE_VALUE = 'office:value';
     public const XML_ATTRIBUTE_BOOLEAN_VALUE = 'office:boolean-value';
@@ -36,24 +51,26 @@ class CellValueFormatter
     public const XML_ATTRIBUTE_CURRENCY = 'office:currency';
     public const XML_ATTRIBUTE_C = 'text:c';
 
-    /** @var bool Whether date/time values should be returned as PHP objects or be formatted as strings */
-    protected $shouldFormatDates;
-
-    /** @var \OpenSpout\Common\Helper\Escaper\ODS Used to unescape XML data */
-    protected $escaper;
-
-    /** @var array List of XML nodes representing whitespaces and their corresponding value */
-    private static $WHITESPACE_XML_NODES = [
+    /**
+     * List of XML nodes representing whitespaces and their corresponding value.
+     */
+    private const WHITESPACE_XML_NODES = [
         self::XML_NODE_TEXT_S => ' ',
         self::XML_NODE_TEXT_TAB => "\t",
         self::XML_NODE_TEXT_LINE_BREAK => "\n",
     ];
 
+    /** @var bool Whether date/time values should be returned as PHP objects or be formatted as strings */
+    private bool $shouldFormatDates;
+
+    /** @var ODS Used to unescape XML data */
+    private ODS $escaper;
+
     /**
-     * @param bool                                 $shouldFormatDates Whether date/time values should be returned as PHP objects or be formatted as strings
-     * @param \OpenSpout\Common\Helper\Escaper\ODS $escaper           Used to unescape XML data
+     * @param bool $shouldFormatDates Whether date/time values should be returned as PHP objects or be formatted as strings
+     * @param ODS  $escaper           Used to unescape XML data
      */
-    public function __construct($shouldFormatDates, $escaper)
+    public function __construct(bool $shouldFormatDates, ODS $escaper)
     {
         $this->shouldFormatDates = $shouldFormatDates;
         $this->escaper = $escaper;
@@ -64,52 +81,32 @@ class CellValueFormatter
      *
      * @see http://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os-part1.html#refTable13
      *
-     * @param \DOMElement $node
+     * @return bool|DateInterval|DateTimeImmutable|float|int|string The value associated with the cell, empty string if cell's type is void/undefined
      *
      * @throws InvalidValueException If the node value is not valid
-     *
-     * @return bool|\DateInterval|\DateTime|float|int|string The value associated with the cell, empty string if cell's type is void/undefined
      */
-    public function extractAndFormatNodeValue($node)
+    public function extractAndFormatNodeValue(DOMElement $node): bool|DateInterval|DateTimeImmutable|float|int|string
     {
         $cellType = $node->getAttribute(self::XML_ATTRIBUTE_TYPE);
 
-        switch ($cellType) {
-            case self::CELL_TYPE_STRING:
-                return $this->formatStringCellValue($node);
-
-            case self::CELL_TYPE_FLOAT:
-                return $this->formatFloatCellValue($node);
-
-            case self::CELL_TYPE_BOOLEAN:
-                return $this->formatBooleanCellValue($node);
-
-            case self::CELL_TYPE_DATE:
-                return $this->formatDateCellValue($node);
-
-            case self::CELL_TYPE_TIME:
-                return $this->formatTimeCellValue($node);
-
-            case self::CELL_TYPE_CURRENCY:
-                return $this->formatCurrencyCellValue($node);
-
-            case self::CELL_TYPE_PERCENTAGE:
-                return $this->formatPercentageCellValue($node);
-
-            case self::CELL_TYPE_VOID:
-            default:
-                return '';
-        }
+        return match ($cellType) {
+            self::CELL_TYPE_STRING => $this->formatStringCellValue($node),
+            self::CELL_TYPE_FLOAT => $this->formatFloatCellValue($node),
+            self::CELL_TYPE_BOOLEAN => $this->formatBooleanCellValue($node),
+            self::CELL_TYPE_DATE => $this->formatDateCellValue($node),
+            self::CELL_TYPE_TIME => $this->formatTimeCellValue($node),
+            self::CELL_TYPE_CURRENCY => $this->formatCurrencyCellValue($node),
+            self::CELL_TYPE_PERCENTAGE => $this->formatPercentageCellValue($node),
+            default => '',
+        };
     }
 
     /**
      * Returns the cell String value.
      *
-     * @param \DOMElement $node
-     *
      * @return string The value associated with the cell
      */
-    protected function formatStringCellValue($node)
+    private function formatStringCellValue(DOMElement $node): string
     {
         $pNodeValues = [];
         $pNodes = $node->getElementsByTagName(self::XML_NODE_P);
@@ -126,11 +123,9 @@ class CellValueFormatter
     /**
      * Returns the cell Numeric value from the given node.
      *
-     * @param \DOMElement $node
-     *
      * @return float|int The value associated with the cell
      */
-    protected function formatFloatCellValue($node)
+    private function formatFloatCellValue(DOMElement $node): float|int
     {
         $nodeValue = $node->getAttribute(self::XML_ATTRIBUTE_VALUE);
 
@@ -143,27 +138,19 @@ class CellValueFormatter
     /**
      * Returns the cell Boolean value from the given node.
      *
-     * @param \DOMElement $node
-     *
      * @return bool The value associated with the cell
      */
-    protected function formatBooleanCellValue($node)
+    private function formatBooleanCellValue(DOMElement $node): bool
     {
-        $nodeValue = $node->getAttribute(self::XML_ATTRIBUTE_BOOLEAN_VALUE);
-
-        return (bool) $nodeValue;
+        return (bool) $node->getAttribute(self::XML_ATTRIBUTE_BOOLEAN_VALUE);
     }
 
     /**
      * Returns the cell Date value from the given node.
      *
-     * @param \DOMElement $node
-     *
      * @throws InvalidValueException If the value is not a valid date
-     *
-     * @return \DateTime|string The value associated with the cell
      */
-    protected function formatDateCellValue($node)
+    private function formatDateCellValue(DOMElement $node): string|DateTimeImmutable
     {
         // The XML node looks like this:
         // <table:table-cell calcext:value-type="date" office:date-value="2016-05-19T16:39:00" office:value-type="date">
@@ -179,9 +166,9 @@ class CellValueFormatter
             $nodeValue = $node->getAttribute(self::XML_ATTRIBUTE_DATE_VALUE);
 
             try {
-                $cellValue = new \DateTime($nodeValue);
-            } catch (\Exception $e) {
-                throw new InvalidValueException($nodeValue);
+                $cellValue = new DateTimeImmutable($nodeValue);
+            } catch (Exception $previous) {
+                throw new InvalidValueException($nodeValue, '', 0, $previous);
             }
         }
 
@@ -191,13 +178,11 @@ class CellValueFormatter
     /**
      * Returns the cell Time value from the given node.
      *
-     * @param \DOMElement $node
+     * @return DateInterval|string The value associated with the cell
      *
      * @throws InvalidValueException If the value is not a valid time
-     *
-     * @return \DateInterval|string The value associated with the cell
      */
-    protected function formatTimeCellValue($node)
+    private function formatTimeCellValue(DOMElement $node): DateInterval|string
     {
         // The XML node looks like this:
         // <table:table-cell calcext:value-type="time" office:time-value="PT13H24M00S" office:value-type="time">
@@ -213,9 +198,9 @@ class CellValueFormatter
             $nodeValue = $node->getAttribute(self::XML_ATTRIBUTE_TIME_VALUE);
 
             try {
-                $cellValue = new \DateInterval($nodeValue);
-            } catch (\Exception $e) {
-                throw new InvalidValueException($nodeValue);
+                $cellValue = new DateInterval($nodeValue);
+            } catch (Exception $previous) {
+                throw new InvalidValueException($nodeValue, '', 0, $previous);
             }
         }
 
@@ -225,11 +210,9 @@ class CellValueFormatter
     /**
      * Returns the cell Currency value from the given node.
      *
-     * @param \DOMElement $node
-     *
      * @return string The value associated with the cell (e.g. "100 USD" or "9.99 EUR")
      */
-    protected function formatCurrencyCellValue($node)
+    private function formatCurrencyCellValue(DOMElement $node): string
     {
         $value = $node->getAttribute(self::XML_ATTRIBUTE_VALUE);
         $currency = $node->getAttribute(self::XML_ATTRIBUTE_CURRENCY);
@@ -240,29 +223,22 @@ class CellValueFormatter
     /**
      * Returns the cell Percentage value from the given node.
      *
-     * @param \DOMElement $node
-     *
      * @return float|int The value associated with the cell
      */
-    protected function formatPercentageCellValue($node)
+    private function formatPercentageCellValue(DOMElement $node): float|int
     {
         // percentages are formatted like floats
         return $this->formatFloatCellValue($node);
     }
 
-    /**
-     * @param \DOMNode $pNode
-     *
-     * @return string
-     */
-    private function extractTextValueFromNode($pNode)
+    private function extractTextValueFromNode(DOMNode $pNode): string
     {
         $textValue = '';
 
         foreach ($pNode->childNodes as $childNode) {
-            if ($childNode instanceof \DOMText) {
+            if ($childNode instanceof DOMText) {
                 $textValue .= $childNode->nodeValue;
-            } elseif ($this->isWhitespaceNode($childNode->nodeName)) {
+            } elseif ($this->isWhitespaceNode($childNode->nodeName) && $childNode instanceof DOMElement) {
                 $textValue .= $this->transformWhitespaceNode($childNode);
             } elseif (self::XML_NODE_TEXT_A === $childNode->nodeName || self::XML_NODE_TEXT_SPAN === $childNode->nodeName) {
                 $textValue .= $this->extractTextValueFromNode($childNode);
@@ -277,14 +253,10 @@ class CellValueFormatter
      *  - <text:s />
      *  - <text:tab />
      *  - <text:line-break />.
-     *
-     * @param string $nodeName
-     *
-     * @return bool
      */
-    private function isWhitespaceNode($nodeName)
+    private function isWhitespaceNode(string $nodeName): bool
     {
-        return isset(self::$WHITESPACE_XML_NODES[$nodeName]);
+        return isset(self::WHITESPACE_XML_NODES[$nodeName]);
     }
 
     /**
@@ -297,15 +269,15 @@ class CellValueFormatter
      *
      * @see https://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os-part1.html#__RefHeading__1415200_253892949
      *
-     * @param \DOMElement $node The XML node representing a whitespace
+     * @param DOMElement $node The XML node representing a whitespace
      *
      * @return string The corresponding whitespace value
      */
-    private function transformWhitespaceNode($node)
+    private function transformWhitespaceNode(DOMElement $node): string
     {
         $countAttribute = $node->getAttribute(self::XML_ATTRIBUTE_C); // only defined for "<text:s>"
-        $numWhitespaces = (!empty($countAttribute)) ? (int) $countAttribute : 1;
+        $numWhitespaces = '' !== $countAttribute ? (int) $countAttribute : 1;
 
-        return str_repeat(self::$WHITESPACE_XML_NODES[$node->nodeName], $numWhitespaces);
+        return str_repeat(self::WHITESPACE_XML_NODES[$node->nodeName], $numWhitespaces);
     }
 }
diff --git a/lib/openspout/src/Reader/ODS/Helper/SettingsHelper.php b/lib/openspout/src/Reader/ODS/Helper/SettingsHelper.php
index 4463eeb3e91..9925e88a08f 100644
--- a/lib/openspout/src/Reader/ODS/Helper/SettingsHelper.php
+++ b/lib/openspout/src/Reader/ODS/Helper/SettingsHelper.php
@@ -1,41 +1,34 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\ODS\Helper;
 
 use OpenSpout\Reader\Exception\XMLProcessingException;
-use OpenSpout\Reader\ODS\Creator\InternalEntityFactory;
+use OpenSpout\Reader\Wrapper\XMLReader;
 
 /**
- * This class provides helper functions to extract data from the "settings.xml" file.
+ * @internal
  */
-class SettingsHelper
+final class SettingsHelper
 {
     public const SETTINGS_XML_FILE_PATH = 'settings.xml';
 
-    /** Definition of XML nodes name and attribute used to parse settings data */
+    /**
+     * Definition of XML nodes name and attribute used to parse settings data.
+     */
     public const XML_NODE_CONFIG_ITEM = 'config:config-item';
     public const XML_ATTRIBUTE_CONFIG_NAME = 'config:name';
     public const XML_ATTRIBUTE_VALUE_ACTIVE_TABLE = 'ActiveTable';
 
-    /** @var InternalEntityFactory Factory to create entities */
-    private $entityFactory;
-
-    /**
-     * @param InternalEntityFactory $entityFactory Factory to create entities
-     */
-    public function __construct($entityFactory)
-    {
-        $this->entityFactory = $entityFactory;
-    }
-
     /**
      * @param string $filePath Path of the file to be read
      *
      * @return null|string Name of the sheet that was defined as active or NULL if none found
      */
-    public function getActiveSheetName($filePath)
+    public function getActiveSheetName(string $filePath): ?string
     {
-        $xmlReader = $this->entityFactory->createXMLReader();
+        $xmlReader = new XMLReader();
         if (false === $xmlReader->openFileInZip($filePath, self::SETTINGS_XML_FILE_PATH)) {
             return null;
         }
@@ -50,7 +43,7 @@ class SettingsHelper
                     break;
                 }
             }
-        } catch (XMLProcessingException $exception) {
+        } catch (XMLProcessingException $exception) {  // @codeCoverageIgnore
             // do nothing
         }
 
diff --git a/lib/openspout/src/Reader/ODS/Manager/OptionsManager.php b/lib/openspout/src/Reader/ODS/Manager/OptionsManager.php
deleted file mode 100644
index e13c5446dc5..00000000000
--- a/lib/openspout/src/Reader/ODS/Manager/OptionsManager.php
+++ /dev/null
@@ -1,32 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\ODS\Manager;
-
-use OpenSpout\Common\Manager\OptionsManagerAbstract;
-use OpenSpout\Reader\Common\Entity\Options;
-
-/**
- * ODS Reader options manager.
- */
-class OptionsManager extends OptionsManagerAbstract
-{
-    /**
-     * {@inheritdoc}
-     */
-    protected function getSupportedOptions()
-    {
-        return [
-            Options::SHOULD_FORMAT_DATES,
-            Options::SHOULD_PRESERVE_EMPTY_ROWS,
-        ];
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function setDefaultOptions()
-    {
-        $this->setOption(Options::SHOULD_FORMAT_DATES, false);
-        $this->setOption(Options::SHOULD_PRESERVE_EMPTY_ROWS, false);
-    }
-}
diff --git a/lib/openspout/src/Reader/ODS/Options.php b/lib/openspout/src/Reader/ODS/Options.php
new file mode 100644
index 00000000000..f7641eabe67
--- /dev/null
+++ b/lib/openspout/src/Reader/ODS/Options.php
@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Reader\ODS;
+
+final class Options
+{
+    public bool $SHOULD_FORMAT_DATES = false;
+    public bool $SHOULD_PRESERVE_EMPTY_ROWS = false;
+}
diff --git a/lib/openspout/src/Reader/ODS/Reader.php b/lib/openspout/src/Reader/ODS/Reader.php
index 8f3970afc4b..80a6852b8e8 100644
--- a/lib/openspout/src/Reader/ODS/Reader.php
+++ b/lib/openspout/src/Reader/ODS/Reader.php
@@ -1,28 +1,43 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\ODS;
 
 use OpenSpout\Common\Exception\IOException;
-use OpenSpout\Reader\ODS\Creator\InternalEntityFactory;
-use OpenSpout\Reader\ReaderAbstract;
+use OpenSpout\Common\Helper\Escaper\ODS;
+use OpenSpout\Reader\AbstractReader;
+use OpenSpout\Reader\ODS\Helper\SettingsHelper;
+use ZipArchive;
 
 /**
- * This class provides support to read data from a ODS file.
+ * @extends AbstractReader<SheetIterator>
  */
-class Reader extends ReaderAbstract
+final class Reader extends AbstractReader
 {
-    /** @var \ZipArchive */
-    protected $zip;
+    private ZipArchive $zip;
+
+    private Options $options;
 
     /** @var SheetIterator To iterator over the ODS sheets */
-    protected $sheetIterator;
+    private SheetIterator $sheetIterator;
+
+    public function __construct(?Options $options = null)
+    {
+        $this->options = $options ?? new Options();
+    }
+
+    public function getSheetIterator(): SheetIterator
+    {
+        $this->ensureStreamOpened();
+
+        return $this->sheetIterator;
+    }
 
     /**
      * Returns whether stream wrappers are supported.
-     *
-     * @return bool
      */
-    protected function doesSupportStreamWrapper()
+    protected function doesSupportStreamWrapper(): bool
     {
         return false;
     }
@@ -35,39 +50,22 @@ class Reader extends ReaderAbstract
      * @throws \OpenSpout\Common\Exception\IOException            If the file at the given path or its content cannot be read
      * @throws \OpenSpout\Reader\Exception\NoSheetsFoundException If there are no sheets in the file
      */
-    protected function openReader($filePath)
+    protected function openReader(string $filePath): void
     {
-        /** @var InternalEntityFactory $entityFactory */
-        $entityFactory = $this->entityFactory;
+        $this->zip = new ZipArchive();
 
-        $this->zip = $entityFactory->createZipArchive();
-
-        if (true === $this->zip->open($filePath)) {
-            /** @var InternalEntityFactory $entityFactory */
-            $entityFactory = $this->entityFactory;
-            $this->sheetIterator = $entityFactory->createSheetIterator($filePath, $this->optionsManager);
-        } else {
+        if (true !== $this->zip->open($filePath)) {
             throw new IOException("Could not open {$filePath} for reading.");
         }
-    }
 
-    /**
-     * Returns an iterator to iterate over sheets.
-     *
-     * @return SheetIterator To iterate over sheets
-     */
-    protected function getConcreteSheetIterator()
-    {
-        return $this->sheetIterator;
+        $this->sheetIterator = new SheetIterator($filePath, $this->options, new ODS(), new SettingsHelper());
     }
 
     /**
      * Closes the reader. To be used after reading the file.
      */
-    protected function closeReader()
+    protected function closeReader(): void
     {
-        if (null !== $this->zip) {
-            $this->zip->close();
-        }
+        $this->zip->close();
     }
 }
diff --git a/lib/openspout/src/Reader/ODS/RowIterator.php b/lib/openspout/src/Reader/ODS/RowIterator.php
index a3ab7aa4fd0..caac67eee85 100644
--- a/lib/openspout/src/Reader/ODS/RowIterator.php
+++ b/lib/openspout/src/Reader/ODS/RowIterator.php
@@ -1,103 +1,79 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\ODS;
 
+use DOMElement;
 use OpenSpout\Common\Entity\Cell;
 use OpenSpout\Common\Entity\Row;
-use OpenSpout\Common\Exception\IOException;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Reader\Common\Entity\Options;
-use OpenSpout\Reader\Common\Manager\RowManager;
 use OpenSpout\Reader\Common\XMLProcessor;
 use OpenSpout\Reader\Exception\InvalidValueException;
 use OpenSpout\Reader\Exception\IteratorNotRewindableException;
-use OpenSpout\Reader\Exception\XMLProcessingException;
-use OpenSpout\Reader\IteratorInterface;
-use OpenSpout\Reader\ODS\Creator\InternalEntityFactory;
 use OpenSpout\Reader\ODS\Helper\CellValueFormatter;
+use OpenSpout\Reader\RowIteratorInterface;
 use OpenSpout\Reader\Wrapper\XMLReader;
 
-class RowIterator implements IteratorInterface
+final class RowIterator implements RowIteratorInterface
 {
-    /** Definition of XML nodes names used to parse data */
+    /**
+     * Definition of XML nodes names used to parse data.
+     */
     public const XML_NODE_TABLE = 'table:table';
     public const XML_NODE_ROW = 'table:table-row';
     public const XML_NODE_CELL = 'table:table-cell';
     public const MAX_COLUMNS_EXCEL = 16384;
 
-    /** Definition of XML attribute used to parse data */
+    /**
+     * Definition of XML attribute used to parse data.
+     */
     public const XML_ATTRIBUTE_NUM_ROWS_REPEATED = 'table:number-rows-repeated';
     public const XML_ATTRIBUTE_NUM_COLUMNS_REPEATED = 'table:number-columns-repeated';
 
-    /** @var \OpenSpout\Reader\Wrapper\XMLReader The XMLReader object that will help read sheet's XML data */
-    protected $xmlReader;
+    private Options $options;
 
-    /** @var \OpenSpout\Reader\Common\XMLProcessor Helper Object to process XML nodes */
-    protected $xmlProcessor;
-
-    /** @var bool Whether empty rows should be returned or skipped */
-    protected $shouldPreserveEmptyRows;
+    /** @var XMLProcessor Helper Object to process XML nodes */
+    private XMLProcessor $xmlProcessor;
 
     /** @var Helper\CellValueFormatter Helper to format cell values */
-    protected $cellValueFormatter;
-
-    /** @var RowManager Manages rows */
-    protected $rowManager;
-
-    /** @var InternalEntityFactory Factory to create entities */
-    protected $entityFactory;
+    private Helper\CellValueFormatter $cellValueFormatter;
 
     /** @var bool Whether the iterator has already been rewound once */
-    protected $hasAlreadyBeenRewound = false;
+    private bool $hasAlreadyBeenRewound = false;
 
     /** @var Row The currently processed row */
-    protected $currentlyProcessedRow;
+    private Row $currentlyProcessedRow;
 
     /** @var null|Row Buffer used to store the current row, while checking if there are more rows to read */
-    protected $rowBuffer;
+    private ?Row $rowBuffer;
 
     /** @var bool Indicates whether all rows have been read */
-    protected $hasReachedEndOfFile = false;
+    private bool $hasReachedEndOfFile = false;
 
     /** @var int Last row index processed (one-based) */
-    protected $lastRowIndexProcessed = 0;
+    private int $lastRowIndexProcessed = 0;
 
     /** @var int Row index to be processed next (one-based) */
-    protected $nextRowIndexToBeProcessed = 1;
+    private int $nextRowIndexToBeProcessed = 1;
 
     /** @var null|Cell Last processed cell (because when reading cell at column N+1, cell N is processed) */
-    protected $lastProcessedCell;
+    private ?Cell $lastProcessedCell;
 
     /** @var int Number of times the last processed row should be repeated */
-    protected $numRowsRepeated = 1;
+    private int $numRowsRepeated = 1;
 
     /** @var int Number of times the last cell value should be copied to the cells on its right */
-    protected $numColumnsRepeated = 1;
+    private int $numColumnsRepeated = 1;
 
     /** @var bool Whether at least one cell has been read for the row currently being processed */
-    protected $hasAlreadyReadOneCellInCurrentRow = false;
+    private bool $hasAlreadyReadOneCellInCurrentRow = false;
 
-    /**
-     * @param XMLReader               $xmlReader          XML Reader, positioned on the "<table:table>" element
-     * @param OptionsManagerInterface $optionsManager     Reader's options manager
-     * @param CellValueFormatter      $cellValueFormatter Helper to format cell values
-     * @param XMLProcessor            $xmlProcessor       Helper to process XML files
-     * @param RowManager              $rowManager         Manages rows
-     * @param InternalEntityFactory   $entityFactory      Factory to create entities
-     */
     public function __construct(
-        XMLReader $xmlReader,
-        OptionsManagerInterface $optionsManager,
+        Options $options,
         CellValueFormatter $cellValueFormatter,
-        XMLProcessor $xmlProcessor,
-        RowManager $rowManager,
-        InternalEntityFactory $entityFactory
+        XMLProcessor $xmlProcessor
     ) {
-        $this->xmlReader = $xmlReader;
-        $this->shouldPreserveEmptyRows = $optionsManager->getOption(Options::SHOULD_PRESERVE_EMPTY_ROWS);
         $this->cellValueFormatter = $cellValueFormatter;
-        $this->entityFactory = $entityFactory;
-        $this->rowManager = $rowManager;
 
         // Register all callbacks to process different nodes when reading the XML file
         $this->xmlProcessor = $xmlProcessor;
@@ -105,6 +81,7 @@ class RowIterator implements IteratorInterface
         $this->xmlProcessor->registerCallback(self::XML_NODE_CELL, XMLProcessor::NODE_TYPE_START, [$this, 'processCellStartingNode']);
         $this->xmlProcessor->registerCallback(self::XML_NODE_ROW, XMLProcessor::NODE_TYPE_END, [$this, 'processRowEndingNode']);
         $this->xmlProcessor->registerCallback(self::XML_NODE_TABLE, XMLProcessor::NODE_TYPE_END, [$this, 'processTableEndingNode']);
+        $this->options = $options;
     }
 
     /**
@@ -115,7 +92,6 @@ class RowIterator implements IteratorInterface
      *
      * @throws \OpenSpout\Reader\Exception\IteratorNotRewindableException If the iterator is rewound more than once
      */
-    #[\ReturnTypeWillChange]
     public function rewind(): void
     {
         // Because sheet and row data is located in the file, we can't rewind both the
@@ -139,7 +115,6 @@ class RowIterator implements IteratorInterface
      *
      * @see http://php.net/manual/en/iterator.valid.php
      */
-    #[\ReturnTypeWillChange]
     public function valid(): bool
     {
         return !$this->hasReachedEndOfFile;
@@ -153,7 +128,6 @@ class RowIterator implements IteratorInterface
      * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If a shared string was not found
      * @throws \OpenSpout\Common\Exception\IOException                   If unable to read the sheet data XML
      */
-    #[\ReturnTypeWillChange]
     public function next(): void
     {
         if ($this->doesNeedDataForNextRowToBeProcessed()) {
@@ -168,7 +142,6 @@ class RowIterator implements IteratorInterface
      *
      * @see http://php.net/manual/en/iterator.current.php
      */
-    #[\ReturnTypeWillChange]
     public function current(): Row
     {
         return $this->rowBuffer;
@@ -179,21 +152,11 @@ class RowIterator implements IteratorInterface
      *
      * @see http://php.net/manual/en/iterator.key.php
      */
-    #[\ReturnTypeWillChange]
     public function key(): int
     {
         return $this->lastRowIndexProcessed;
     }
 
-    /**
-     * Cleans up what was created to iterate over the object.
-     */
-    #[\ReturnTypeWillChange]
-    public function end(): void
-    {
-        $this->xmlReader->close();
-    }
-
     /**
      * Returns whether we need data for the next row to be processed.
      * We DO need to read data if:
@@ -203,7 +166,7 @@ class RowIterator implements IteratorInterface
      *
      * @return bool whether we need data for the next row to be processed
      */
-    protected function doesNeedDataForNextRowToBeProcessed()
+    private function doesNeedDataForNextRowToBeProcessed(): bool
     {
         $hasReadAtLeastOneRow = (0 !== $this->lastRowIndexProcessed);
 
@@ -217,25 +180,21 @@ class RowIterator implements IteratorInterface
      * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If a shared string was not found
      * @throws \OpenSpout\Common\Exception\IOException                   If unable to read the sheet data XML
      */
-    protected function readDataForNextRow()
+    private function readDataForNextRow(): void
     {
-        $this->currentlyProcessedRow = $this->entityFactory->createRow();
+        $this->currentlyProcessedRow = new Row([], null);
 
-        try {
-            $this->xmlProcessor->readUntilStopped();
-        } catch (XMLProcessingException $exception) {
-            throw new IOException("The sheet's data cannot be read. [{$exception->getMessage()}]");
-        }
+        $this->xmlProcessor->readUntilStopped();
 
         $this->rowBuffer = $this->currentlyProcessedRow;
     }
 
     /**
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XMLReader object, positioned on a "<table:table-row>" starting node
+     * @param XMLReader $xmlReader XMLReader object, positioned on a "<table:table-row>" starting node
      *
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processRowStartingNode($xmlReader)
+    private function processRowStartingNode(XMLReader $xmlReader): int
     {
         // Reset data from current row
         $this->hasAlreadyReadOneCellInCurrentRow = false;
@@ -247,16 +206,16 @@ class RowIterator implements IteratorInterface
     }
 
     /**
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XMLReader object, positioned on a "<table:table-cell>" starting node
+     * @param XMLReader $xmlReader XMLReader object, positioned on a "<table:table-cell>" starting node
      *
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processCellStartingNode($xmlReader)
+    private function processCellStartingNode(XMLReader $xmlReader): int
     {
         $currentNumColumnsRepeated = $this->getNumColumnsRepeatedForCurrentNode($xmlReader);
 
         // NOTE: expand() will automatically decode all XML entities of the child nodes
-        /** @var \DOMElement $node */
+        /** @var DOMElement $node */
         $node = $xmlReader->expand();
         $currentCell = $this->getCell($node);
 
@@ -277,12 +236,12 @@ class RowIterator implements IteratorInterface
     /**
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processRowEndingNode()
+    private function processRowEndingNode(): int
     {
         $isEmptyRow = $this->isEmptyRow($this->currentlyProcessedRow, $this->lastProcessedCell);
 
         // if the fetched row is empty and we don't want to preserve it...
-        if (!$this->shouldPreserveEmptyRows && $isEmptyRow) {
+        if (!$this->options->SHOULD_PRESERVE_EMPTY_ROWS && $isEmptyRow) {
             // ... skip it
             return XMLProcessor::PROCESSING_CONTINUE;
         }
@@ -315,7 +274,7 @@ class RowIterator implements IteratorInterface
     /**
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processTableEndingNode()
+    private function processTableEndingNode(): int
     {
         // The closing "</table:table>" marks the end of the file
         $this->hasReachedEndOfFile = true;
@@ -324,11 +283,11 @@ class RowIterator implements IteratorInterface
     }
 
     /**
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XMLReader object, positioned on a "<table:table-row>" starting node
+     * @param XMLReader $xmlReader XMLReader object, positioned on a "<table:table-row>" starting node
      *
      * @return int The value of "table:number-rows-repeated" attribute of the current node, or 1 if attribute missing
      */
-    protected function getNumRowsRepeatedForCurrentNode($xmlReader)
+    private function getNumRowsRepeatedForCurrentNode(XMLReader $xmlReader): int
     {
         $numRowsRepeated = $xmlReader->getAttribute(self::XML_ATTRIBUTE_NUM_ROWS_REPEATED);
 
@@ -336,11 +295,11 @@ class RowIterator implements IteratorInterface
     }
 
     /**
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XMLReader object, positioned on a "<table:table-cell>" starting node
+     * @param XMLReader $xmlReader XMLReader object, positioned on a "<table:table-cell>" starting node
      *
      * @return int The value of "table:number-columns-repeated" attribute of the current node, or 1 if attribute missing
      */
-    protected function getNumColumnsRepeatedForCurrentNode($xmlReader)
+    private function getNumColumnsRepeatedForCurrentNode(XMLReader $xmlReader): int
     {
         $numColumnsRepeated = $xmlReader->getAttribute(self::XML_ATTRIBUTE_NUM_COLUMNS_REPEATED);
 
@@ -350,18 +309,15 @@ class RowIterator implements IteratorInterface
     /**
      * Returns the cell with (unescaped) correctly marshalled, cell value associated to the given XML node.
      *
-     * @param \DOMElement $node
-     *
      * @return Cell The cell set with the associated with the cell
      */
-    protected function getCell($node)
+    private function getCell(DOMElement $node): Cell
     {
         try {
             $cellValue = $this->cellValueFormatter->extractAndFormatNodeValue($node);
-            $cell = $this->entityFactory->createCell($cellValue);
+            $cell = Cell::fromValue($cellValue);
         } catch (InvalidValueException $exception) {
-            $cell = $this->entityFactory->createCell($exception->getInvalidValue());
-            $cell->setType(Cell::TYPE_ERROR);
+            $cell = new Cell\ErrorCell($exception->getInvalidValue(), null);
         }
 
         return $cell;
@@ -373,16 +329,15 @@ class RowIterator implements IteratorInterface
      * After finishing processing each cell, the last read cell is not part of the
      * row data yet (as we still need to apply the "num-columns-repeated" attribute).
      *
-     * @param Row       $currentRow
      * @param null|Cell $lastReadCell The last read cell
      *
      * @return bool Whether the row is empty
      */
-    protected function isEmptyRow($currentRow, $lastReadCell)
+    private function isEmptyRow(Row $currentRow, ?Cell $lastReadCell): bool
     {
         return
-            $this->rowManager->isEmpty($currentRow)
-            && (!isset($lastReadCell) || $lastReadCell->isEmpty())
+            $currentRow->isEmpty()
+            && (null === $lastReadCell || $lastReadCell instanceof Cell\EmptyCell)
         ;
     }
 }
diff --git a/lib/openspout/src/Reader/ODS/Sheet.php b/lib/openspout/src/Reader/ODS/Sheet.php
index 306f2688834..7f71d0a09e0 100644
--- a/lib/openspout/src/Reader/ODS/Sheet.php
+++ b/lib/openspout/src/Reader/ODS/Sheet.php
@@ -1,31 +1,30 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\ODS;
 
-use OpenSpout\Reader\SheetInterface;
+use OpenSpout\Reader\SheetWithVisibilityInterface;
 
 /**
- * Represents a sheet within a ODS file.
+ * @implements SheetWithVisibilityInterface<RowIterator>
  */
-class Sheet implements SheetInterface
+final class Sheet implements SheetWithVisibilityInterface
 {
-    /** @var \OpenSpout\Reader\ODS\RowIterator To iterate over sheet's rows */
-    protected $rowIterator;
-
-    /** @var int ID of the sheet */
-    protected $id;
+    /** @var RowIterator To iterate over sheet's rows */
+    private RowIterator $rowIterator;
 
     /** @var int Index of the sheet, based on order in the workbook (zero-based) */
-    protected $index;
+    private int $index;
 
     /** @var string Name of the sheet */
-    protected $name;
+    private string $name;
 
     /** @var bool Whether the sheet was the active one */
-    protected $isActive;
+    private bool $isActive;
 
     /** @var bool Whether the sheet is visible */
-    protected $isVisible;
+    private bool $isVisible;
 
     /**
      * @param RowIterator $rowIterator    The corresponding row iterator
@@ -34,7 +33,7 @@ class Sheet implements SheetInterface
      * @param bool        $isSheetActive  Whether the sheet was defined as active
      * @param bool        $isSheetVisible Whether the sheet is visible
      */
-    public function __construct($rowIterator, $sheetIndex, $sheetName, $isSheetActive, $isSheetVisible)
+    public function __construct(RowIterator $rowIterator, int $sheetIndex, string $sheetName, bool $isSheetActive, bool $isSheetVisible)
     {
         $this->rowIterator = $rowIterator;
         $this->index = $sheetIndex;
@@ -43,10 +42,7 @@ class Sheet implements SheetInterface
         $this->isVisible = $isSheetVisible;
     }
 
-    /**
-     * @return \OpenSpout\Reader\ODS\RowIterator
-     */
-    public function getRowIterator()
+    public function getRowIterator(): RowIterator
     {
         return $this->rowIterator;
     }
@@ -54,7 +50,7 @@ class Sheet implements SheetInterface
     /**
      * @return int Index of the sheet, based on order in the workbook (zero-based)
      */
-    public function getIndex()
+    public function getIndex(): int
     {
         return $this->index;
     }
@@ -62,7 +58,7 @@ class Sheet implements SheetInterface
     /**
      * @return string Name of the sheet
      */
-    public function getName()
+    public function getName(): string
     {
         return $this->name;
     }
@@ -70,7 +66,7 @@ class Sheet implements SheetInterface
     /**
      * @return bool Whether the sheet was defined as active
      */
-    public function isActive()
+    public function isActive(): bool
     {
         return $this->isActive;
     }
@@ -78,7 +74,7 @@ class Sheet implements SheetInterface
     /**
      * @return bool Whether the sheet is visible
      */
-    public function isVisible()
+    public function isVisible(): bool
     {
         return $this->isVisible;
     }
diff --git a/lib/openspout/src/Reader/ODS/SheetIterator.php b/lib/openspout/src/Reader/ODS/SheetIterator.php
index 5240e3873d2..d0d40f508f3 100644
--- a/lib/openspout/src/Reader/ODS/SheetIterator.php
+++ b/lib/openspout/src/Reader/ODS/SheetIterator.php
@@ -1,24 +1,31 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\ODS;
 
+use DOMElement;
 use OpenSpout\Common\Exception\IOException;
+use OpenSpout\Common\Helper\Escaper\ODS;
+use OpenSpout\Reader\Common\XMLProcessor;
 use OpenSpout\Reader\Exception\XMLProcessingException;
-use OpenSpout\Reader\IteratorInterface;
-use OpenSpout\Reader\ODS\Creator\InternalEntityFactory;
+use OpenSpout\Reader\ODS\Helper\CellValueFormatter;
 use OpenSpout\Reader\ODS\Helper\SettingsHelper;
+use OpenSpout\Reader\SheetIteratorInterface;
 use OpenSpout\Reader\Wrapper\XMLReader;
 
 /**
- * Iterate over ODS sheet.
+ * @implements SheetIteratorInterface<Sheet>
  */
-class SheetIterator implements IteratorInterface
+final class SheetIterator implements SheetIteratorInterface
 {
     public const CONTENT_XML_FILE_PATH = 'content.xml';
 
     public const XML_STYLE_NAMESPACE = 'urn:oasis:names:tc:opendocument:xmlns:style:1.0';
 
-    /** Definition of XML nodes name and attribute used to parse sheet data */
+    /**
+     * Definition of XML nodes name and attribute used to parse sheet data.
+     */
     public const XML_NODE_AUTOMATIC_STYLES = 'office:automatic-styles';
     public const XML_NODE_STYLE_TABLE_PROPERTIES = 'table-properties';
     public const XML_NODE_TABLE = 'table:table';
@@ -28,45 +35,37 @@ class SheetIterator implements IteratorInterface
     public const XML_ATTRIBUTE_TABLE_DISPLAY = 'table:display';
 
     /** @var string Path of the file to be read */
-    protected $filePath;
+    private string $filePath;
 
-    /** @var \OpenSpout\Common\Manager\OptionsManagerInterface Reader's options manager */
-    protected $optionsManager;
-
-    /** @var InternalEntityFactory Factory to create entities */
-    protected $entityFactory;
+    private Options $options;
 
     /** @var XMLReader The XMLReader object that will help read sheet's XML data */
-    protected $xmlReader;
+    private XMLReader $xmlReader;
 
-    /** @var \OpenSpout\Common\Helper\Escaper\ODS Used to unescape XML data */
-    protected $escaper;
+    /** @var ODS Used to unescape XML data */
+    private ODS $escaper;
 
     /** @var bool Whether there are still at least a sheet to be read */
-    protected $hasFoundSheet;
+    private bool $hasFoundSheet;
 
     /** @var int The index of the sheet being read (zero-based) */
-    protected $currentSheetIndex;
+    private int $currentSheetIndex;
 
     /** @var string The name of the sheet that was defined as active */
-    protected $activeSheetName;
+    private ?string $activeSheetName;
 
-    /** @var array Associative array [STYLE_NAME] => [IS_SHEET_VISIBLE] */
-    protected $sheetsVisibility;
+    /** @var array<string, bool> Associative array [STYLE_NAME] => [IS_SHEET_VISIBLE] */
+    private array $sheetsVisibility;
 
-    /**
-     * @param string                                            $filePath       Path of the file to be read
-     * @param \OpenSpout\Common\Manager\OptionsManagerInterface $optionsManager
-     * @param \OpenSpout\Common\Helper\Escaper\ODS              $escaper        Used to unescape XML data
-     * @param SettingsHelper                                    $settingsHelper Helper to get data from "settings.xml"
-     * @param InternalEntityFactory                             $entityFactory  Factory to create entities
-     */
-    public function __construct($filePath, $optionsManager, $escaper, $settingsHelper, $entityFactory)
-    {
+    public function __construct(
+        string $filePath,
+        Options $options,
+        ODS $escaper,
+        SettingsHelper $settingsHelper
+    ) {
         $this->filePath = $filePath;
-        $this->optionsManager = $optionsManager;
-        $this->entityFactory = $entityFactory;
-        $this->xmlReader = $entityFactory->createXMLReader();
+        $this->options = $options;
+        $this->xmlReader = new XMLReader();
         $this->escaper = $escaper;
         $this->activeSheetName = $settingsHelper->getActiveSheetName($filePath);
     }
@@ -78,8 +77,7 @@ class SheetIterator implements IteratorInterface
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to open the XML file containing sheets' data
      */
-    #[\ReturnTypeWillChange]
-    public function rewind()
+    public function rewind(): void
     {
         $this->xmlReader->close();
 
@@ -103,13 +101,15 @@ class SheetIterator implements IteratorInterface
      * Checks if current position is valid.
      *
      * @see http://php.net/manual/en/iterator.valid.php
-     *
-     * @return bool
      */
-    #[\ReturnTypeWillChange]
-    public function valid()
+    public function valid(): bool
     {
-        return $this->hasFoundSheet;
+        $valid = $this->hasFoundSheet;
+        if (!$valid) {
+            $this->xmlReader->close();
+        }
+
+        return $valid;
     }
 
     /**
@@ -117,8 +117,7 @@ class SheetIterator implements IteratorInterface
      *
      * @see http://php.net/manual/en/iterator.next.php
      */
-    #[\ReturnTypeWillChange]
-    public function next()
+    public function next(): void
     {
         $this->hasFoundSheet = $this->xmlReader->readUntilNodeFound(self::XML_NODE_TABLE);
 
@@ -131,27 +130,29 @@ class SheetIterator implements IteratorInterface
      * Return the current element.
      *
      * @see http://php.net/manual/en/iterator.current.php
-     *
-     * @return \OpenSpout\Reader\ODS\Sheet
      */
-    #[\ReturnTypeWillChange]
-    public function current()
+    public function current(): Sheet
     {
         $escapedSheetName = $this->xmlReader->getAttribute(self::XML_ATTRIBUTE_TABLE_NAME);
+        \assert(null !== $escapedSheetName);
         $sheetName = $this->escaper->unescape($escapedSheetName);
 
         $isSheetActive = $this->isSheetActive($sheetName, $this->currentSheetIndex, $this->activeSheetName);
 
         $sheetStyleName = $this->xmlReader->getAttribute(self::XML_ATTRIBUTE_TABLE_STYLE_NAME);
+        \assert(null !== $sheetStyleName);
         $isSheetVisible = $this->isSheetVisible($sheetStyleName);
 
-        return $this->entityFactory->createSheet(
-            $this->xmlReader,
+        return new Sheet(
+            new RowIterator(
+                $this->options,
+                new CellValueFormatter($this->options->SHOULD_FORMAT_DATES, new ODS()),
+                new XMLProcessor($this->xmlReader)
+            ),
             $this->currentSheetIndex,
             $sheetName,
             $isSheetActive,
-            $isSheetVisible,
-            $this->optionsManager
+            $isSheetVisible
         );
     }
 
@@ -159,44 +160,33 @@ class SheetIterator implements IteratorInterface
      * Return the key of the current element.
      *
      * @see http://php.net/manual/en/iterator.key.php
-     *
-     * @return int
      */
-    #[\ReturnTypeWillChange]
-    public function key()
+    public function key(): int
     {
         return $this->currentSheetIndex + 1;
     }
 
-    /**
-     * Cleans up what was created to iterate over the object.
-     */
-    #[\ReturnTypeWillChange]
-    public function end()
-    {
-        $this->xmlReader->close();
-    }
-
     /**
      * Extracts the visibility of the sheets.
      *
-     * @return array Associative array [STYLE_NAME] => [IS_SHEET_VISIBLE]
+     * @return array<string, bool> Associative array [STYLE_NAME] => [IS_SHEET_VISIBLE]
      */
-    private function readSheetsVisibility()
+    private function readSheetsVisibility(): array
     {
         $sheetsVisibility = [];
 
         $this->xmlReader->readUntilNodeFound(self::XML_NODE_AUTOMATIC_STYLES);
-        /** @var \DOMElement $automaticStylesNode */
+
         $automaticStylesNode = $this->xmlReader->expand();
+        \assert($automaticStylesNode instanceof DOMElement);
 
         $tableStyleNodes = $automaticStylesNode->getElementsByTagNameNS(self::XML_STYLE_NAMESPACE, self::XML_NODE_STYLE_TABLE_PROPERTIES);
 
-        /** @var \DOMElement $tableStyleNode */
         foreach ($tableStyleNodes as $tableStyleNode) {
             $isSheetVisible = ('false' !== $tableStyleNode->getAttribute(self::XML_ATTRIBUTE_TABLE_DISPLAY));
 
             $parentStyleNode = $tableStyleNode->parentNode;
+            \assert($parentStyleNode instanceof DOMElement);
             $styleName = $parentStyleNode->getAttribute(self::XML_ATTRIBUTE_STYLE_NAME);
 
             $sheetsVisibility[$styleName] = $isSheetVisible;
@@ -214,7 +204,7 @@ class SheetIterator implements IteratorInterface
      *
      * @return bool Whether the current sheet was defined as the active one
      */
-    private function isSheetActive($sheetName, $sheetIndex, $activeSheetName)
+    private function isSheetActive(string $sheetName, int $sheetIndex, ?string $activeSheetName): bool
     {
         // The given sheet is active if its name matches the defined active sheet's name
         // or if no information about the active sheet was found, it defaults to the first sheet.
@@ -231,7 +221,7 @@ class SheetIterator implements IteratorInterface
      *
      * @return bool Whether the current sheet is visible
      */
-    private function isSheetVisible($sheetStyleName)
+    private function isSheetVisible(string $sheetStyleName): bool
     {
         return $this->sheetsVisibility[$sheetStyleName] ??
             true;
diff --git a/lib/openspout/src/Reader/ReaderInterface.php b/lib/openspout/src/Reader/ReaderInterface.php
index a1d9f74d73e..146bdf88c62 100644
--- a/lib/openspout/src/Reader/ReaderInterface.php
+++ b/lib/openspout/src/Reader/ReaderInterface.php
@@ -1,9 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader;
 
 /**
- * Interface ReaderInterface.
+ * @template T of SheetIteratorInterface
  */
 interface ReaderInterface
 {
@@ -15,19 +17,19 @@ interface ReaderInterface
      *
      * @throws \OpenSpout\Common\Exception\IOException
      */
-    public function open($filePath);
+    public function open(string $filePath): void;
 
     /**
      * Returns an iterator to iterate over sheets.
      *
-     * @throws \OpenSpout\Reader\Exception\ReaderNotOpenedException If called before opening the reader
+     * @return T
      *
-     * @return SheetIteratorInterface To iterate over sheets
+     * @throws \OpenSpout\Reader\Exception\ReaderNotOpenedException If called before opening the reader
      */
-    public function getSheetIterator();
+    public function getSheetIterator(): SheetIteratorInterface;
 
     /**
      * Closes the reader, preventing any additional reading.
      */
-    public function close();
+    public function close(): void;
 }
diff --git a/lib/openspout/src/Reader/RowIteratorInterface.php b/lib/openspout/src/Reader/RowIteratorInterface.php
index 1d7c0a68294..b810af233b3 100644
--- a/lib/openspout/src/Reader/RowIteratorInterface.php
+++ b/lib/openspout/src/Reader/RowIteratorInterface.php
@@ -4,19 +4,13 @@ declare(strict_types=1);
 
 namespace OpenSpout\Reader;
 
+use Iterator;
 use OpenSpout\Common\Entity\Row;
 
-interface RowIteratorInterface extends IteratorInterface
+/**
+ * @extends Iterator<Row>
+ */
+interface RowIteratorInterface extends Iterator
 {
-    /**
-     * Cleans up what was created to iterate over the object.
-     */
-    #[\ReturnTypeWillChange]
-    public function end();
-
-    /**
-     * @return null|Row
-     */
-    #[\ReturnTypeWillChange]
-    public function current();
+    public function current(): ?Row;
 }
diff --git a/lib/openspout/src/Reader/SheetInterface.php b/lib/openspout/src/Reader/SheetInterface.php
index 985b136e75c..ebd41e3b128 100644
--- a/lib/openspout/src/Reader/SheetInterface.php
+++ b/lib/openspout/src/Reader/SheetInterface.php
@@ -1,34 +1,31 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader;
 
 /**
- * Interface SheetInterface.
+ * @template T of RowIteratorInterface
  */
 interface SheetInterface
 {
     /**
-     * @return IteratorInterface iterator to iterate over the sheet's rows
+     * @return T iterator to iterate over the sheet's rows
      */
-    public function getRowIterator();
+    public function getRowIterator(): RowIteratorInterface;
 
     /**
      * @return int Index of the sheet
      */
-    public function getIndex();
+    public function getIndex(): int;
 
     /**
      * @return string Name of the sheet
      */
-    public function getName();
+    public function getName(): string;
 
     /**
      * @return bool Whether the sheet was defined as active
      */
-    public function isActive();
-
-    /**
-     * @return bool Whether the sheet is visible
-     */
-    public function isVisible();
+    public function isActive(): bool;
 }
diff --git a/lib/openspout/src/Reader/SheetIteratorInterface.php b/lib/openspout/src/Reader/SheetIteratorInterface.php
index a3936f1d640..42f83ffb73e 100644
--- a/lib/openspout/src/Reader/SheetIteratorInterface.php
+++ b/lib/openspout/src/Reader/SheetIteratorInterface.php
@@ -4,20 +4,17 @@ declare(strict_types=1);
 
 namespace OpenSpout\Reader;
 
+use Iterator;
+
 /**
- * Interface IteratorInterface.
+ * @template T of SheetInterface
+ *
+ * @extends Iterator<T>
  */
-interface SheetIteratorInterface extends IteratorInterface
+interface SheetIteratorInterface extends Iterator
 {
     /**
-     * Cleans up what was created to iterate over the object.
+     * @return T of SheetInterface
      */
-    #[\ReturnTypeWillChange]
-    public function end();
-
-    /**
-     * @return null|SheetInterface
-     */
-    #[\ReturnTypeWillChange]
-    public function current();
+    public function current(): SheetInterface;
 }
diff --git a/lib/openspout/src/Reader/SheetWithVisibilityInterface.php b/lib/openspout/src/Reader/SheetWithVisibilityInterface.php
new file mode 100644
index 00000000000..e4566045762
--- /dev/null
+++ b/lib/openspout/src/Reader/SheetWithVisibilityInterface.php
@@ -0,0 +1,18 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Reader;
+
+/**
+ * @template T of RowIteratorInterface
+ *
+ * @extends SheetInterface<T>
+ */
+interface SheetWithVisibilityInterface extends SheetInterface
+{
+    /**
+     * @return bool Whether the sheet is visible
+     */
+    public function isVisible(): bool;
+}
diff --git a/lib/openspout/src/Reader/Wrapper/XMLInternalErrorsHelper.php b/lib/openspout/src/Reader/Wrapper/XMLInternalErrorsHelper.php
index 788e732a5bb..971750c5c7e 100644
--- a/lib/openspout/src/Reader/Wrapper/XMLInternalErrorsHelper.php
+++ b/lib/openspout/src/Reader/Wrapper/XMLInternalErrorsHelper.php
@@ -1,22 +1,24 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Wrapper;
 
 use OpenSpout\Reader\Exception\XMLProcessingException;
 
 /**
- * Trait XMLInternalErrorsHelper.
+ * @internal
  */
 trait XMLInternalErrorsHelper
 {
     /** @var bool Stores whether XML errors were initially stored internally - used to reset */
-    protected $initialUseInternalErrorsValue;
+    private bool $initialUseInternalErrorsValue;
 
     /**
      * To avoid displaying lots of warning/error messages on screen,
      * stores errors internally instead.
      */
-    protected function useXMLInternalErrors()
+    private function useXMLInternalErrors(): void
     {
         libxml_clear_errors();
         $this->initialUseInternalErrorsValue = libxml_use_internal_errors(true);
@@ -28,7 +30,7 @@ trait XMLInternalErrorsHelper
      *
      * @throws \OpenSpout\Reader\Exception\XMLProcessingException
      */
-    protected function resetXMLInternalErrorsSettingAndThrowIfXMLErrorOccured()
+    private function resetXMLInternalErrorsSettingAndThrowIfXMLErrorOccured(): void
     {
         if ($this->hasXMLErrorOccured()) {
             $this->resetXMLInternalErrorsSetting();
@@ -39,7 +41,7 @@ trait XMLInternalErrorsHelper
         $this->resetXMLInternalErrorsSetting();
     }
 
-    protected function resetXMLInternalErrorsSetting()
+    private function resetXMLInternalErrorsSetting(): void
     {
         libxml_use_internal_errors($this->initialUseInternalErrorsValue);
     }
@@ -49,7 +51,7 @@ trait XMLInternalErrorsHelper
      *
      * @return bool TRUE if an error occured, FALSE otherwise
      */
-    private function hasXMLErrorOccured()
+    private function hasXMLErrorOccured(): bool
     {
         return false !== libxml_get_last_error();
     }
@@ -59,11 +61,11 @@ trait XMLInternalErrorsHelper
      *
      * @see libxml_get_last_error
      *
-     * @return null|string Last XML error message or null if no error
+     * @return string Last XML error message or null if no error
      */
-    private function getLastXMLErrorMessage()
+    private function getLastXMLErrorMessage(): string
     {
-        $errorMessage = null;
+        $errorMessage = '';
         $error = libxml_get_last_error();
 
         if (false !== $error) {
diff --git a/lib/openspout/src/Reader/Wrapper/XMLReader.php b/lib/openspout/src/Reader/Wrapper/XMLReader.php
index 946ca27f632..8fa9663f12c 100644
--- a/lib/openspout/src/Reader/Wrapper/XMLReader.php
+++ b/lib/openspout/src/Reader/Wrapper/XMLReader.php
@@ -1,13 +1,15 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\Wrapper;
 
+use ZipArchive;
+
 /**
- * Wrapper around the built-in XMLReader.
- *
- * @see \XMLReader
+ * @internal
  */
-class XMLReader extends \XMLReader
+final class XMLReader extends \XMLReader
 {
     use XMLInternalErrorsHelper;
 
@@ -21,14 +23,13 @@ class XMLReader extends \XMLReader
      *
      * @return bool TRUE on success or FALSE on failure
      */
-    public function openFileInZip($zipFilePath, $fileInsideZipPath)
+    public function openFileInZip(string $zipFilePath, string $fileInsideZipPath): bool
     {
         $wasOpenSuccessful = false;
         $realPathURI = $this->getRealPathURIForFileInZip($zipFilePath, $fileInsideZipPath);
 
         // We need to check first that the file we are trying to read really exist because:
         //  - PHP emits a warning when trying to open a file that does not exist.
-        //  - HHVM does not check if file exists within zip file (@link https://github.com/facebook/hhvm/issues/5779)
         if ($this->fileExistsWithinZip($realPathURI)) {
             $wasOpenSuccessful = $this->open($realPathURI, null, LIBXML_NONET);
         }
@@ -45,7 +46,7 @@ class XMLReader extends \XMLReader
      *
      * @return string The real path URI
      */
-    public function getRealPathURIForFileInZip($zipFilePath, $fileInsideZipPath)
+    public function getRealPathURIForFileInZip(string $zipFilePath, string $fileInsideZipPath): string
     {
         // The file path should not start with a '/', otherwise it won't be found
         $fileInsideZipPathWithoutLeadingSlash = ltrim($fileInsideZipPath, '/');
@@ -59,11 +60,8 @@ class XMLReader extends \XMLReader
      * @see \XMLReader::read
      *
      * @throws \OpenSpout\Reader\Exception\XMLProcessingException If an error/warning occurred
-     *
-     * @return bool TRUE on success or FALSE on failure
      */
-    #[\ReturnTypeWillChange]
-    public function read()
+    public function read(): bool
     {
         $this->useXMLInternalErrors();
 
@@ -79,11 +77,11 @@ class XMLReader extends \XMLReader
      *
      * @param string $nodeName Name of the node to find
      *
-     * @throws \OpenSpout\Reader\Exception\XMLProcessingException If an error/warning occurred
-     *
      * @return bool TRUE on success or FALSE on failure
+     *
+     * @throws \OpenSpout\Reader\Exception\XMLProcessingException If an error/warning occurred
      */
-    public function readUntilNodeFound($nodeName)
+    public function readUntilNodeFound(string $nodeName): bool
     {
         do {
             $wasReadSuccessful = $this->read();
@@ -101,11 +99,8 @@ class XMLReader extends \XMLReader
      * @param null|string $localName The name of the next node to move to
      *
      * @throws \OpenSpout\Reader\Exception\XMLProcessingException If an error/warning occurred
-     *
-     * @return bool TRUE on success or FALSE on failure
      */
-    #[\ReturnTypeWillChange]
-    public function next($localName = null)
+    public function next($localName = null): bool
     {
         $this->useXMLInternalErrors();
 
@@ -117,21 +112,17 @@ class XMLReader extends \XMLReader
     }
 
     /**
-     * @param string $nodeName
-     *
      * @return bool Whether the XML Reader is currently positioned on the starting node with given name
      */
-    public function isPositionedOnStartingNode($nodeName)
+    public function isPositionedOnStartingNode(string $nodeName): bool
     {
         return $this->isPositionedOnNode($nodeName, self::ELEMENT);
     }
 
     /**
-     * @param string $nodeName
-     *
      * @return bool Whether the XML Reader is currently positioned on the ending node with given name
      */
-    public function isPositionedOnEndingNode($nodeName)
+    public function isPositionedOnEndingNode(string $nodeName): bool
     {
         return $this->isPositionedOnNode($nodeName, self::END_ELEMENT);
     }
@@ -139,7 +130,7 @@ class XMLReader extends \XMLReader
     /**
      * @return string The name of the current node, un-prefixed
      */
-    public function getCurrentNodeName()
+    public function getCurrentNodeName(): string
     {
         return $this->localName;
     }
@@ -151,16 +142,16 @@ class XMLReader extends \XMLReader
      *
      * @return bool TRUE if the file exists, FALSE otherwise
      */
-    protected function fileExistsWithinZip($zipStreamURI)
+    private function fileExistsWithinZip(string $zipStreamURI): bool
     {
         $doesFileExists = false;
 
         $pattern = '/zip:\/\/([^#]+)#(.*)/';
-        if (preg_match($pattern, $zipStreamURI, $matches)) {
+        if (1 === preg_match($pattern, $zipStreamURI, $matches)) {
             $zipFilePath = $matches[1];
             $innerFilePath = $matches[2];
 
-            $zip = new \ZipArchive();
+            $zip = new ZipArchive();
             if (true === $zip->open($zipFilePath)) {
                 $doesFileExists = (false !== $zip->locateName($innerFilePath));
                 $zip->close();
@@ -171,12 +162,9 @@ class XMLReader extends \XMLReader
     }
 
     /**
-     * @param string $nodeName
-     * @param int    $nodeType
-     *
      * @return bool Whether the XML Reader is currently positioned on the node with given name and type
      */
-    private function isPositionedOnNode($nodeName, $nodeType)
+    private function isPositionedOnNode(string $nodeName, int $nodeType): bool
     {
         /**
          * In some cases, the node has a prefix (for instance, "<sheet>" can also be "<x:sheet>").
@@ -184,7 +172,7 @@ class XMLReader extends \XMLReader
          *
          * @see https://github.com/box/spout/issues/233
          */
-        $hasPrefix = (false !== strpos($nodeName, ':'));
+        $hasPrefix = str_contains($nodeName, ':');
         $currentNodeName = ($hasPrefix) ? $this->name : $this->localName;
 
         return $this->nodeType === $nodeType && $currentNodeName === $nodeName;
diff --git a/lib/openspout/src/Reader/XLSX/Creator/HelperFactory.php b/lib/openspout/src/Reader/XLSX/Creator/HelperFactory.php
deleted file mode 100644
index 3528b23e6e8..00000000000
--- a/lib/openspout/src/Reader/XLSX/Creator/HelperFactory.php
+++ /dev/null
@@ -1,38 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\XLSX\Creator;
-
-use OpenSpout\Common\Helper\Escaper;
-use OpenSpout\Reader\XLSX\Helper\CellValueFormatter;
-use OpenSpout\Reader\XLSX\Manager\SharedStringsManager;
-use OpenSpout\Reader\XLSX\Manager\StyleManager;
-
-/**
- * Factory to create helpers.
- */
-class HelperFactory extends \OpenSpout\Common\Creator\HelperFactory
-{
-    /**
-     * @param SharedStringsManager $sharedStringsManager Manages shared strings
-     * @param StyleManager         $styleManager         Manages styles
-     * @param bool                 $shouldFormatDates    Whether date/time values should be returned as PHP objects or be formatted as strings
-     * @param bool                 $shouldUse1904Dates   Whether date/time values should use a calendar starting in 1904 instead of 1900
-     *
-     * @return CellValueFormatter
-     */
-    public function createCellValueFormatter($sharedStringsManager, $styleManager, $shouldFormatDates, $shouldUse1904Dates)
-    {
-        $escaper = $this->createStringsEscaper();
-
-        return new CellValueFormatter($sharedStringsManager, $styleManager, $shouldFormatDates, $shouldUse1904Dates, $escaper);
-    }
-
-    /**
-     * @return Escaper\XLSX
-     */
-    public function createStringsEscaper()
-    {
-        // @noinspection PhpUnnecessaryFullyQualifiedNameInspection
-        return new Escaper\XLSX();
-    }
-}
diff --git a/lib/openspout/src/Reader/XLSX/Creator/InternalEntityFactory.php b/lib/openspout/src/Reader/XLSX/Creator/InternalEntityFactory.php
deleted file mode 100644
index 33b18df6fb3..00000000000
--- a/lib/openspout/src/Reader/XLSX/Creator/InternalEntityFactory.php
+++ /dev/null
@@ -1,163 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\XLSX\Creator;
-
-use OpenSpout\Common\Entity\Cell;
-use OpenSpout\Common\Entity\Row;
-use OpenSpout\Reader\Common\Creator\InternalEntityFactoryInterface;
-use OpenSpout\Reader\Common\Entity\Options;
-use OpenSpout\Reader\Common\XMLProcessor;
-use OpenSpout\Reader\Wrapper\XMLReader;
-use OpenSpout\Reader\XLSX\Manager\SharedStringsManager;
-use OpenSpout\Reader\XLSX\RowIterator;
-use OpenSpout\Reader\XLSX\Sheet;
-use OpenSpout\Reader\XLSX\SheetIterator;
-
-/**
- * Factory to create entities.
- */
-class InternalEntityFactory implements InternalEntityFactoryInterface
-{
-    /** @var HelperFactory */
-    private $helperFactory;
-
-    /** @var ManagerFactory */
-    private $managerFactory;
-
-    public function __construct(ManagerFactory $managerFactory, HelperFactory $helperFactory)
-    {
-        $this->managerFactory = $managerFactory;
-        $this->helperFactory = $helperFactory;
-    }
-
-    /**
-     * @param string                                            $filePath             Path of the file to be read
-     * @param \OpenSpout\Common\Manager\OptionsManagerInterface $optionsManager       Reader's options manager
-     * @param SharedStringsManager                              $sharedStringsManager Manages shared strings
-     *
-     * @return SheetIterator
-     */
-    public function createSheetIterator($filePath, $optionsManager, $sharedStringsManager)
-    {
-        $sheetManager = $this->managerFactory->createSheetManager(
-            $filePath,
-            $optionsManager,
-            $sharedStringsManager,
-            $this
-        );
-
-        return new SheetIterator($sheetManager);
-    }
-
-    /**
-     * @param string                                            $filePath             Path of the XLSX file being read
-     * @param string                                            $sheetDataXMLFilePath Path of the sheet data XML file as in [Content_Types].xml
-     * @param int                                               $sheetIndex           Index of the sheet, based on order in the workbook (zero-based)
-     * @param string                                            $sheetName            Name of the sheet
-     * @param bool                                              $isSheetActive        Whether the sheet was defined as active
-     * @param bool                                              $isSheetVisible       Whether the sheet is visible
-     * @param \OpenSpout\Common\Manager\OptionsManagerInterface $optionsManager       Reader's options manager
-     * @param SharedStringsManager                              $sharedStringsManager Manages shared strings
-     *
-     * @return Sheet
-     */
-    public function createSheet(
-        $filePath,
-        $sheetDataXMLFilePath,
-        $sheetIndex,
-        $sheetName,
-        $isSheetActive,
-        $isSheetVisible,
-        $optionsManager,
-        $sharedStringsManager
-    ) {
-        $rowIterator = $this->createRowIterator($filePath, $sheetDataXMLFilePath, $optionsManager, $sharedStringsManager);
-
-        return new Sheet($rowIterator, $sheetIndex, $sheetName, $isSheetActive, $isSheetVisible);
-    }
-
-    /**
-     * @param Cell[] $cells
-     *
-     * @return Row
-     */
-    public function createRow(array $cells = [])
-    {
-        return new Row($cells, null);
-    }
-
-    /**
-     * @param mixed $cellValue
-     *
-     * @return Cell
-     */
-    public function createCell($cellValue)
-    {
-        return new Cell($cellValue);
-    }
-
-    /**
-     * @return \ZipArchive
-     */
-    public function createZipArchive()
-    {
-        return new \ZipArchive();
-    }
-
-    /**
-     * @return XMLReader
-     */
-    public function createXMLReader()
-    {
-        return new XMLReader();
-    }
-
-    /**
-     * @param XMLReader $xmlReader
-     *
-     * @return XMLProcessor
-     */
-    public function createXMLProcessor($xmlReader)
-    {
-        return new XMLProcessor($xmlReader);
-    }
-
-    /**
-     * @param string                                            $filePath             Path of the XLSX file being read
-     * @param string                                            $sheetDataXMLFilePath Path of the sheet data XML file as in [Content_Types].xml
-     * @param \OpenSpout\Common\Manager\OptionsManagerInterface $optionsManager       Reader's options manager
-     * @param SharedStringsManager                              $sharedStringsManager Manages shared strings
-     *
-     * @return RowIterator
-     */
-    private function createRowIterator($filePath, $sheetDataXMLFilePath, $optionsManager, $sharedStringsManager)
-    {
-        $xmlReader = $this->createXMLReader();
-        $xmlProcessor = $this->createXMLProcessor($xmlReader);
-
-        $styleManager = $this->managerFactory->createStyleManager($filePath, $this);
-        $rowManager = $this->managerFactory->createRowManager($this);
-        $shouldFormatDates = $optionsManager->getOption(Options::SHOULD_FORMAT_DATES);
-        $shouldUse1904Dates = $optionsManager->getOption(Options::SHOULD_USE_1904_DATES);
-
-        $cellValueFormatter = $this->helperFactory->createCellValueFormatter(
-            $sharedStringsManager,
-            $styleManager,
-            $shouldFormatDates,
-            $shouldUse1904Dates
-        );
-
-        $shouldPreserveEmptyRows = $optionsManager->getOption(Options::SHOULD_PRESERVE_EMPTY_ROWS);
-
-        return new RowIterator(
-            $filePath,
-            $sheetDataXMLFilePath,
-            $shouldPreserveEmptyRows,
-            $xmlReader,
-            $xmlProcessor,
-            $cellValueFormatter,
-            $rowManager,
-            $this
-        );
-    }
-}
diff --git a/lib/openspout/src/Reader/XLSX/Creator/ManagerFactory.php b/lib/openspout/src/Reader/XLSX/Creator/ManagerFactory.php
deleted file mode 100644
index 10a8833a4e9..00000000000
--- a/lib/openspout/src/Reader/XLSX/Creator/ManagerFactory.php
+++ /dev/null
@@ -1,109 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\XLSX\Creator;
-
-use OpenSpout\Reader\Common\Manager\RowManager;
-use OpenSpout\Reader\XLSX\Manager\SharedStringsCaching\CachingStrategyFactory;
-use OpenSpout\Reader\XLSX\Manager\SharedStringsManager;
-use OpenSpout\Reader\XLSX\Manager\SheetManager;
-use OpenSpout\Reader\XLSX\Manager\StyleManager;
-use OpenSpout\Reader\XLSX\Manager\WorkbookRelationshipsManager;
-
-/**
- * Factory to create managers.
- */
-class ManagerFactory
-{
-    /** @var HelperFactory */
-    private $helperFactory;
-
-    /** @var CachingStrategyFactory */
-    private $cachingStrategyFactory;
-
-    /** @var null|WorkbookRelationshipsManager */
-    private $cachedWorkbookRelationshipsManager;
-
-    /**
-     * @param HelperFactory          $helperFactory          Factory to create helpers
-     * @param CachingStrategyFactory $cachingStrategyFactory Factory to create shared strings caching strategies
-     */
-    public function __construct(HelperFactory $helperFactory, CachingStrategyFactory $cachingStrategyFactory)
-    {
-        $this->helperFactory = $helperFactory;
-        $this->cachingStrategyFactory = $cachingStrategyFactory;
-    }
-
-    /**
-     * @param string                $filePath      Path of the XLSX file being read
-     * @param string                $tempFolder    Temporary folder where the temporary files to store shared strings will be stored
-     * @param InternalEntityFactory $entityFactory Factory to create entities
-     *
-     * @return SharedStringsManager
-     */
-    public function createSharedStringsManager($filePath, $tempFolder, $entityFactory)
-    {
-        $workbookRelationshipsManager = $this->createWorkbookRelationshipsManager($filePath, $entityFactory);
-
-        return new SharedStringsManager(
-            $filePath,
-            $tempFolder,
-            $workbookRelationshipsManager,
-            $entityFactory,
-            $this->helperFactory,
-            $this->cachingStrategyFactory
-        );
-    }
-
-    /**
-     * @param string                                              $filePath             Path of the XLSX file being read
-     * @param \OpenSpout\Common\Manager\OptionsManagerInterface   $optionsManager       Reader's options manager
-     * @param \OpenSpout\Reader\XLSX\Manager\SharedStringsManager $sharedStringsManager Manages shared strings
-     * @param InternalEntityFactory                               $entityFactory        Factory to create entities
-     *
-     * @return SheetManager
-     */
-    public function createSheetManager($filePath, $optionsManager, $sharedStringsManager, $entityFactory)
-    {
-        $escaper = $this->helperFactory->createStringsEscaper();
-
-        return new SheetManager($filePath, $optionsManager, $sharedStringsManager, $escaper, $entityFactory);
-    }
-
-    /**
-     * @param string                $filePath      Path of the XLSX file being read
-     * @param InternalEntityFactory $entityFactory Factory to create entities
-     *
-     * @return StyleManager
-     */
-    public function createStyleManager($filePath, $entityFactory)
-    {
-        $workbookRelationshipsManager = $this->createWorkbookRelationshipsManager($filePath, $entityFactory);
-
-        return new StyleManager($filePath, $workbookRelationshipsManager, $entityFactory);
-    }
-
-    /**
-     * @param InternalEntityFactory $entityFactory Factory to create entities
-     *
-     * @return RowManager
-     */
-    public function createRowManager($entityFactory)
-    {
-        return new RowManager($entityFactory);
-    }
-
-    /**
-     * @param string                $filePath      Path of the XLSX file being read
-     * @param InternalEntityFactory $entityFactory Factory to create entities
-     *
-     * @return WorkbookRelationshipsManager
-     */
-    private function createWorkbookRelationshipsManager($filePath, $entityFactory)
-    {
-        if (!isset($this->cachedWorkbookRelationshipsManager)) {
-            $this->cachedWorkbookRelationshipsManager = new WorkbookRelationshipsManager($filePath, $entityFactory);
-        }
-
-        return $this->cachedWorkbookRelationshipsManager;
-    }
-}
diff --git a/lib/openspout/src/Reader/XLSX/Helper/CellHelper.php b/lib/openspout/src/Reader/XLSX/Helper/CellHelper.php
index 827d728ba57..19c4c248df2 100644
--- a/lib/openspout/src/Reader/XLSX/Helper/CellHelper.php
+++ b/lib/openspout/src/Reader/XLSX/Helper/CellHelper.php
@@ -1,16 +1,18 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX\Helper;
 
 use OpenSpout\Common\Exception\InvalidArgumentException;
 
 /**
- * This class provides helper functions when working with cells.
+ * @internal
  */
-class CellHelper
+final class CellHelper
 {
     // Using ord() is super slow... Using a pre-computed hash table instead.
-    private static $columnLetterToIndexMapping = [
+    private const columnLetterToIndexMapping = [
         'A' => 0, 'B' => 1, 'C' => 2, 'D' => 3, 'E' => 4, 'F' => 5, 'G' => 6,
         'H' => 7, 'I' => 8, 'J' => 9, 'K' => 10, 'L' => 11, 'M' => 12, 'N' => 13,
         'O' => 14, 'P' => 15, 'Q' => 16, 'R' => 17, 'S' => 18, 'T' => 19, 'U' => 20,
@@ -26,10 +28,8 @@ class CellHelper
      * @param string $cellIndex The Excel cell index ('A1', 'BC13', ...)
      *
      * @throws \OpenSpout\Common\Exception\InvalidArgumentException When the given cell index is invalid
-     *
-     * @return int
      */
-    public static function getColumnIndexFromCellIndex($cellIndex)
+    public static function getColumnIndexFromCellIndex(string $cellIndex): int
     {
         if (!self::isValidCellIndex($cellIndex)) {
             throw new InvalidArgumentException('Cannot get column index from an invalid cell index.');
@@ -48,21 +48,21 @@ class CellHelper
         // Also, not using the pow() function because it's slooooow...
         switch ($columnLength) {
             case 1:
-                $columnIndex = (self::$columnLetterToIndexMapping[$columnLetters]);
+                $columnIndex = self::columnLetterToIndexMapping[$columnLetters];
 
                 break;
 
             case 2:
-                $firstLetterIndex = (self::$columnLetterToIndexMapping[$columnLetters[0]] + 1) * 26;
-                $secondLetterIndex = self::$columnLetterToIndexMapping[$columnLetters[1]];
+                $firstLetterIndex = (self::columnLetterToIndexMapping[$columnLetters[0]] + 1) * 26;
+                $secondLetterIndex = self::columnLetterToIndexMapping[$columnLetters[1]];
                 $columnIndex = $firstLetterIndex + $secondLetterIndex;
 
                 break;
 
             case 3:
-                $firstLetterIndex = (self::$columnLetterToIndexMapping[$columnLetters[0]] + 1) * 676;
-                $secondLetterIndex = (self::$columnLetterToIndexMapping[$columnLetters[1]] + 1) * 26;
-                $thirdLetterIndex = self::$columnLetterToIndexMapping[$columnLetters[2]];
+                $firstLetterIndex = (self::columnLetterToIndexMapping[$columnLetters[0]] + 1) * 676;
+                $secondLetterIndex = (self::columnLetterToIndexMapping[$columnLetters[1]] + 1) * 26;
+                $thirdLetterIndex = self::columnLetterToIndexMapping[$columnLetters[2]];
                 $columnIndex = $firstLetterIndex + $secondLetterIndex + $thirdLetterIndex;
 
                 break;
@@ -77,10 +77,8 @@ class CellHelper
      * There can only be 3 letters, as there can only be 16,384 rows, which is equivalent to 'XFE'.
      *
      * @param string $cellIndex The Excel cell index ('A1', 'BC13', ...)
-     *
-     * @return bool
      */
-    protected static function isValidCellIndex($cellIndex)
+    private static function isValidCellIndex(string $cellIndex): bool
     {
         return 1 === preg_match('/^[A-Z]{1,3}\d+$/', $cellIndex);
     }
diff --git a/lib/openspout/src/Reader/XLSX/Helper/CellValueFormatter.php b/lib/openspout/src/Reader/XLSX/Helper/CellValueFormatter.php
index 1734fb5aab2..9f15fb48091 100644
--- a/lib/openspout/src/Reader/XLSX/Helper/CellValueFormatter.php
+++ b/lib/openspout/src/Reader/XLSX/Helper/CellValueFormatter.php
@@ -1,17 +1,25 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX\Helper;
 
+use DateTimeImmutable;
+use DOMElement;
+use Exception;
+use OpenSpout\Common\Helper\Escaper\XLSX;
 use OpenSpout\Reader\Exception\InvalidValueException;
 use OpenSpout\Reader\XLSX\Manager\SharedStringsManager;
-use OpenSpout\Reader\XLSX\Manager\StyleManager;
+use OpenSpout\Reader\XLSX\Manager\StyleManagerInterface;
 
 /**
  * This class provides helper functions to format cell values.
  */
-class CellValueFormatter
+final class CellValueFormatter
 {
-    /** Definition of all possible cell types */
+    /**
+     * Definition of all possible cell types.
+     */
     public const CELL_TYPE_INLINE_STRING = 'inlineStr';
     public const CELL_TYPE_STR = 'str';
     public const CELL_TYPE_SHARED_STRING = 's';
@@ -20,41 +28,52 @@ class CellValueFormatter
     public const CELL_TYPE_DATE = 'd';
     public const CELL_TYPE_ERROR = 'e';
 
-    /** Definition of XML nodes names used to parse data */
+    /**
+     * Definition of XML nodes names used to parse data.
+     */
     public const XML_NODE_VALUE = 'v';
     public const XML_NODE_INLINE_STRING_VALUE = 't';
 
-    /** Definition of XML attributes used to parse data */
+    /**
+     * Definition of XML attributes used to parse data.
+     */
     public const XML_ATTRIBUTE_TYPE = 't';
     public const XML_ATTRIBUTE_STYLE_ID = 's';
 
-    /** Constants used for date formatting */
+    /**
+     * Constants used for date formatting.
+     */
     public const NUM_SECONDS_IN_ONE_DAY = 86400;
 
     /** @var SharedStringsManager Manages shared strings */
-    protected $sharedStringsManager;
+    private SharedStringsManager $sharedStringsManager;
 
-    /** @var StyleManager Manages styles */
-    protected $styleManager;
+    /** @var StyleManagerInterface Manages styles */
+    private StyleManagerInterface $styleManager;
 
     /** @var bool Whether date/time values should be returned as PHP objects or be formatted as strings */
-    protected $shouldFormatDates;
+    private bool $shouldFormatDates;
 
     /** @var bool Whether date/time values should use a calendar starting in 1904 instead of 1900 */
-    protected $shouldUse1904Dates;
+    private bool $shouldUse1904Dates;
 
-    /** @var \OpenSpout\Common\Helper\Escaper\XLSX Used to unescape XML data */
-    protected $escaper;
+    /** @var XLSX Used to unescape XML data */
+    private XLSX $escaper;
 
     /**
-     * @param SharedStringsManager                  $sharedStringsManager Manages shared strings
-     * @param StyleManager                          $styleManager         Manages styles
-     * @param bool                                  $shouldFormatDates    Whether date/time values should be returned as PHP objects or be formatted as strings
-     * @param bool                                  $shouldUse1904Dates   Whether date/time values should use a calendar starting in 1904 instead of 1900
-     * @param \OpenSpout\Common\Helper\Escaper\XLSX $escaper              Used to unescape XML data
+     * @param SharedStringsManager  $sharedStringsManager Manages shared strings
+     * @param StyleManagerInterface $styleManager         Manages styles
+     * @param bool                  $shouldFormatDates    Whether date/time values should be returned as PHP objects or be formatted as strings
+     * @param bool                  $shouldUse1904Dates   Whether date/time values should use a calendar starting in 1904 instead of 1900
+     * @param XLSX                  $escaper              Used to unescape XML data
      */
-    public function __construct($sharedStringsManager, $styleManager, $shouldFormatDates, $shouldUse1904Dates, $escaper)
-    {
+    public function __construct(
+        SharedStringsManager $sharedStringsManager,
+        StyleManagerInterface $styleManager,
+        bool $shouldFormatDates,
+        bool $shouldUse1904Dates,
+        XLSX $escaper
+    ) {
         $this->sharedStringsManager = $sharedStringsManager;
         $this->styleManager = $styleManager;
         $this->shouldFormatDates = $shouldFormatDates;
@@ -65,13 +84,11 @@ class CellValueFormatter
     /**
      * Returns the (unescaped) correctly marshalled, cell value associated to the given XML node.
      *
-     * @param \DOMElement $node
+     * @return bool|DateTimeImmutable|float|int|string The value associated with the cell
      *
      * @throws InvalidValueException If the value is not valid
-     *
-     * @return bool|\DateTime|float|int|string The value associated with the cell
      */
-    public function extractAndFormatNodeValue($node)
+    public function extractAndFormatNodeValue(DOMElement $node): bool|DateTimeImmutable|float|int|string
     {
         // Default cell type is "n"
         $cellType = $node->getAttribute(self::XML_ATTRIBUTE_TYPE) ?: self::CELL_TYPE_NUMERIC;
@@ -82,54 +99,37 @@ class CellValueFormatter
             return $vNodeValue;
         }
 
-        switch ($cellType) {
-            case self::CELL_TYPE_INLINE_STRING:
-                return $this->formatInlineStringCellValue($node);
-
-            case self::CELL_TYPE_SHARED_STRING:
-                return $this->formatSharedStringCellValue($vNodeValue);
-
-            case self::CELL_TYPE_STR:
-                return $this->formatStrCellValue($vNodeValue);
-
-            case self::CELL_TYPE_BOOLEAN:
-                return $this->formatBooleanCellValue($vNodeValue);
-
-            case self::CELL_TYPE_NUMERIC:
-                return $this->formatNumericCellValue($vNodeValue, $cellStyleId);
-
-            case self::CELL_TYPE_DATE:
-                return $this->formatDateCellValue($vNodeValue);
-
-            default:
-                throw new InvalidValueException($vNodeValue);
-        }
+        return match ($cellType) {
+            self::CELL_TYPE_INLINE_STRING => $this->formatInlineStringCellValue($node),
+            self::CELL_TYPE_SHARED_STRING => $this->formatSharedStringCellValue($vNodeValue),
+            self::CELL_TYPE_STR => $this->formatStrCellValue($vNodeValue),
+            self::CELL_TYPE_BOOLEAN => $this->formatBooleanCellValue($vNodeValue),
+            self::CELL_TYPE_NUMERIC => $this->formatNumericCellValue($vNodeValue, $cellStyleId),
+            self::CELL_TYPE_DATE => $this->formatDateCellValue($vNodeValue),
+            default => throw new InvalidValueException($vNodeValue),
+        };
     }
 
     /**
      * Returns the cell's string value from a node's nested value node.
      *
-     * @param \DOMElement $node
-     *
      * @return string The value associated with the cell
      */
-    protected function getVNodeValue($node)
+    private function getVNodeValue(DOMElement $node): string
     {
         // for cell types having a "v" tag containing the value.
         // if not, the returned value should be empty string.
         $vNode = $node->getElementsByTagName(self::XML_NODE_VALUE)->item(0);
 
-        return (null !== $vNode) ? $vNode->nodeValue : '';
+        return (string) $vNode?->nodeValue;
     }
 
     /**
      * Returns the cell String value where string is inline.
      *
-     * @param \DOMElement $node
-     *
      * @return string The value associated with the cell
      */
-    protected function formatInlineStringCellValue($node)
+    private function formatInlineStringCellValue(DOMElement $node): string
     {
         // inline strings are formatted this way (they can contain any number of <t> nodes):
         // <c r="A1" t="inlineStr"><is><t>[INLINE_STRING]</t><t>[INLINE_STRING_2]</t></is></c>
@@ -137,8 +137,9 @@ class CellValueFormatter
 
         $cellValue = '';
         for ($i = 0; $i < $tNodes->count(); ++$i) {
-            $tNode = $tNodes->item($i);
-            $cellValue .= $this->escaper->unescape($tNode->nodeValue);
+            $nodeValue = $tNodes->item($i)->nodeValue;
+            \assert(null !== $nodeValue);
+            $cellValue .= $this->escaper->unescape($nodeValue);
         }
 
         return $cellValue;
@@ -147,11 +148,9 @@ class CellValueFormatter
     /**
      * Returns the cell String value from shared-strings file using nodeValue index.
      *
-     * @param string $nodeValue
-     *
      * @return string The value associated with the cell
      */
-    protected function formatSharedStringCellValue($nodeValue)
+    private function formatSharedStringCellValue(string $nodeValue): string
     {
         // shared strings are formatted this way:
         // <c r="A1" t="s"><v>[SHARED_STRING_INDEX]</v></c>
@@ -164,11 +163,9 @@ class CellValueFormatter
     /**
      * Returns the cell String value, where string is stored in value node.
      *
-     * @param string $nodeValue
-     *
      * @return string The value associated with the cell
      */
-    protected function formatStrCellValue($nodeValue)
+    private function formatStrCellValue(string $nodeValue): string
     {
         $escapedCellValue = trim($nodeValue);
 
@@ -179,12 +176,9 @@ class CellValueFormatter
      * Returns the cell Numeric value from string of nodeValue.
      * The value can also represent a timestamp and a DateTime will be returned.
      *
-     * @param string $nodeValue
-     * @param int    $cellStyleId 0 being the default style
-     *
-     * @return \DateTime|float|int The value associated with the cell
+     * @param int $cellStyleId 0 being the default style
      */
-    protected function formatNumericCellValue($nodeValue, $cellStyleId)
+    private function formatNumericCellValue(int|float|string $nodeValue, int $cellStyleId): DateTimeImmutable|float|int|string
     {
         // Numeric values can represent numbers as well as timestamps.
         // We need to look at the style of the cell to determine whether it is one or the other.
@@ -207,36 +201,27 @@ class CellValueFormatter
      *       Dec 30th 1899, 1900 or Jan 1st, 1904, depending on the Workbook setting.
      * NOTE: The timestamp can also represent a time, if it is a value between 0 and 1.
      *
-     * @see ECMA-376 Part 1 - §18.17.4
-     *
-     * @param float $nodeValue
-     * @param int   $cellStyleId 0 being the default style
+     * @param int $cellStyleId 0 being the default style
      *
      * @throws InvalidValueException If the value is not a valid timestamp
      *
-     * @return \DateTime The value associated with the cell
+     * @see ECMA-376 Part 1 - §18.17.4
      */
-    protected function formatExcelTimestampValue($nodeValue, $cellStyleId)
+    private function formatExcelTimestampValue(float $nodeValue, int $cellStyleId): string|DateTimeImmutable
     {
-        if ($this->isValidTimestampValue($nodeValue)) {
-            $cellValue = $this->formatExcelTimestampValueAsDateTimeValue($nodeValue, $cellStyleId);
-        } else {
-            throw new InvalidValueException($nodeValue);
+        if (!$this->isValidTimestampValue($nodeValue)) {
+            throw new InvalidValueException((string) $nodeValue);
         }
 
-        return $cellValue;
+        return $this->formatExcelTimestampValueAsDateTimeValue($nodeValue, $cellStyleId);
     }
 
     /**
      * Returns whether the given timestamp is supported by SpreadsheetML.
      *
      * @see ECMA-376 Part 1 - §18.17.4 - this specifies the timestamp boundaries.
-     *
-     * @param float $timestampValue
-     *
-     * @return bool
      */
-    protected function isValidTimestampValue($timestampValue)
+    private function isValidTimestampValue(float $timestampValue): bool
     {
         // @NOTE: some versions of Excel don't support negative dates (e.g. Excel for Mac 2011)
         return
@@ -250,22 +235,32 @@ class CellValueFormatter
      * Only the time value matters. The date part is set to the base Excel date:
      * Dec 30th 1899, 1900 or Jan 1st, 1904, depending on the Workbook setting.
      *
-     * @param float $nodeValue
-     * @param int   $cellStyleId 0 being the default style
-     *
-     * @return \DateTime|string The value associated with the cell
+     * @param int $cellStyleId 0 being the default style
      */
-    protected function formatExcelTimestampValueAsDateTimeValue($nodeValue, $cellStyleId)
+    private function formatExcelTimestampValueAsDateTimeValue(float $nodeValue, int $cellStyleId): string|DateTimeImmutable
     {
         $baseDate = $this->shouldUse1904Dates ? '1904-01-01' : '1899-12-30';
 
         $daysSinceBaseDate = (int) $nodeValue;
+        $daysSign = '+';
+        if ($daysSinceBaseDate < 0) {
+            $daysSinceBaseDate = abs($daysSinceBaseDate);
+            $daysSign = '-';
+        }
         $timeRemainder = fmod($nodeValue, 1);
         $secondsRemainder = round($timeRemainder * self::NUM_SECONDS_IN_ONE_DAY, 0);
+        $secondsSign = '+';
+        if ($secondsRemainder < 0) {
+            $secondsRemainder = abs($secondsRemainder);
+            $secondsSign = '-';
+        }
 
-        $dateObj = \DateTime::createFromFormat('|Y-m-d', $baseDate);
-        $dateObj->modify('+'.$daysSinceBaseDate.'days');
-        $dateObj->modify('+'.$secondsRemainder.'seconds');
+        $dateObj = DateTimeImmutable::createFromFormat('|Y-m-d', $baseDate);
+        \assert(false !== $dateObj);
+        $dateObj = $dateObj->modify($daysSign.$daysSinceBaseDate.'days');
+        \assert(false !== $dateObj);
+        $dateObj = $dateObj->modify($secondsSign.$secondsRemainder.'seconds');
+        \assert(false !== $dateObj);
 
         if ($this->shouldFormatDates) {
             $styleNumberFormatCode = $this->styleManager->getNumberFormatCode($cellStyleId);
@@ -281,11 +276,9 @@ class CellValueFormatter
     /**
      * Returns the cell Boolean value from a specific node's Value.
      *
-     * @param string $nodeValue
-     *
      * @return bool The value associated with the cell
      */
-    protected function formatBooleanCellValue($nodeValue)
+    private function formatBooleanCellValue(string $nodeValue): bool
     {
         return (bool) $nodeValue;
     }
@@ -298,16 +291,14 @@ class CellValueFormatter
      * @param string $nodeValue ISO 8601 Date string
      *
      * @throws InvalidValueException If the value is not a valid date
-     *
-     * @return \DateTime|string The value associated with the cell
      */
-    protected function formatDateCellValue($nodeValue)
+    private function formatDateCellValue(string $nodeValue): string|DateTimeImmutable
     {
         // Mitigate thrown Exception on invalid date-time format (http://php.net/manual/en/datetime.construct.php)
         try {
-            $cellValue = ($this->shouldFormatDates) ? $nodeValue : new \DateTime($nodeValue);
-        } catch (\Exception $e) {
-            throw new InvalidValueException($nodeValue);
+            $cellValue = ($this->shouldFormatDates) ? $nodeValue : new DateTimeImmutable($nodeValue);
+        } catch (Exception $exception) {
+            throw new InvalidValueException($nodeValue, '', 0, $exception);
         }
 
         return $cellValue;
diff --git a/lib/openspout/src/Reader/XLSX/Helper/DateFormatHelper.php b/lib/openspout/src/Reader/XLSX/Helper/DateFormatHelper.php
index 78fc4f43cb2..5b6fba79b97 100644
--- a/lib/openspout/src/Reader/XLSX/Helper/DateFormatHelper.php
+++ b/lib/openspout/src/Reader/XLSX/Helper/DateFormatHelper.php
@@ -1,11 +1,13 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX\Helper;
 
 /**
- * This class provides helper functions to format Excel dates.
+ * @internal
  */
-class DateFormatHelper
+final class DateFormatHelper
 {
     public const KEY_GENERAL = 'general';
     public const KEY_HOUR_12 = '12h';
@@ -14,10 +16,9 @@ class DateFormatHelper
     /**
      * This map is used to replace Excel format characters by their PHP equivalent.
      * Keys should be ordered from longest to smallest.
-     *
-     * @var array Mapping between Excel format characters and PHP format characters
+     * Mapping between Excel format characters and PHP format characters.
      */
-    private static $excelDateFormatToPHPDateFormatMapping = [
+    private const excelDateFormatToPHPDateFormatMapping = [
         self::KEY_GENERAL => [
             // Time
             'am/pm' => 'A',  // Uppercase Ante meridiem and Post meridiem
@@ -57,12 +58,13 @@ class DateFormatHelper
      *
      * @return string PHP date format (as defined here: http://php.net/manual/en/function.date.php)
      */
-    public static function toPHPDateFormat($excelDateFormat)
+    public static function toPHPDateFormat(string $excelDateFormat): string
     {
         // Remove brackets potentially present at the beginning of the format string
         // and text portion of the format at the end of it (starting with ";")
         // See §18.8.31 of ECMA-376 for more detail.
         $dateFormat = preg_replace('/^(?:\[\$[^\]]+?\])?([^;]*).*/', '$1', $excelDateFormat);
+        \assert(null !== $dateFormat);
 
         // Double quotes are used to escape characters that must not be interpreted.
         // For instance, ["Day " dd] should result in "Day 13" and we should not try to interpret "D", "a", "y"
@@ -83,13 +85,13 @@ class DateFormatHelper
             $transformedPart = str_replace('\\', '', $transformedPart);
 
             // Apply general transformation first...
-            $transformedPart = strtr($transformedPart, self::$excelDateFormatToPHPDateFormatMapping[self::KEY_GENERAL]);
+            $transformedPart = strtr($transformedPart, self::excelDateFormatToPHPDateFormatMapping[self::KEY_GENERAL]);
 
             // ... then apply hour transformation, for 12-hour or 24-hour format
             if (self::has12HourFormatMarker($dateFormatPart)) {
-                $transformedPart = strtr($transformedPart, self::$excelDateFormatToPHPDateFormatMapping[self::KEY_HOUR_12]);
+                $transformedPart = strtr($transformedPart, self::excelDateFormatToPHPDateFormatMapping[self::KEY_HOUR_12]);
             } else {
-                $transformedPart = strtr($transformedPart, self::$excelDateFormatToPHPDateFormatMapping[self::KEY_HOUR_24]);
+                $transformedPart = strtr($transformedPart, self::excelDateFormatToPHPDateFormatMapping[self::KEY_HOUR_24]);
             }
 
             // overwrite the parts array with the new transformed part
@@ -102,9 +104,10 @@ class DateFormatHelper
         // Finally, to have the date format compatible with the DateTime::format() function, we need to escape
         // all characters that are inside double quotes (and double quotes must be removed).
         // For instance, ["Day " dd] should become [\D\a\y\ dd]
-        return preg_replace_callback('/"(.+?)"/', function ($matches) {
+        return preg_replace_callback('/"(.+?)"/', static function ($matches): string {
             $stringToEscape = $matches[1];
             $letters = preg_split('//u', $stringToEscape, -1, PREG_SPLIT_NO_EMPTY);
+            \assert(false !== $letters);
 
             return '\\'.implode('\\', $letters);
         }, $phpDateFormat);
@@ -115,7 +118,7 @@ class DateFormatHelper
      *
      * @return bool Whether the given date format has the 12-hour format marker
      */
-    private static function has12HourFormatMarker($excelDateFormat)
+    private static function has12HourFormatMarker(string $excelDateFormat): bool
     {
         return false !== stripos($excelDateFormat, 'am/pm');
     }
diff --git a/lib/openspout/src/Reader/XLSX/Manager/OptionsManager.php b/lib/openspout/src/Reader/XLSX/Manager/OptionsManager.php
deleted file mode 100644
index b04b92c816b..00000000000
--- a/lib/openspout/src/Reader/XLSX/Manager/OptionsManager.php
+++ /dev/null
@@ -1,36 +0,0 @@
-<?php
-
-namespace OpenSpout\Reader\XLSX\Manager;
-
-use OpenSpout\Common\Manager\OptionsManagerAbstract;
-use OpenSpout\Reader\Common\Entity\Options;
-
-/**
- * XLSX Reader options manager.
- */
-class OptionsManager extends OptionsManagerAbstract
-{
-    /**
-     * {@inheritdoc}
-     */
-    protected function getSupportedOptions()
-    {
-        return [
-            Options::TEMP_FOLDER,
-            Options::SHOULD_FORMAT_DATES,
-            Options::SHOULD_PRESERVE_EMPTY_ROWS,
-            Options::SHOULD_USE_1904_DATES,
-        ];
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function setDefaultOptions()
-    {
-        $this->setOption(Options::TEMP_FOLDER, sys_get_temp_dir());
-        $this->setOption(Options::SHOULD_FORMAT_DATES, false);
-        $this->setOption(Options::SHOULD_PRESERVE_EMPTY_ROWS, false);
-        $this->setOption(Options::SHOULD_USE_1904_DATES, false);
-    }
-}
diff --git a/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/CachingStrategyFactory.php b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/CachingStrategyFactory.php
index c2f8c9fd52f..3ec42cdc434 100644
--- a/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/CachingStrategyFactory.php
+++ b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/CachingStrategyFactory.php
@@ -1,10 +1,13 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX\Manager\SharedStringsCaching;
 
-use OpenSpout\Reader\XLSX\Creator\HelperFactory;
-
-class CachingStrategyFactory
+/**
+ * @internal
+ */
+final class CachingStrategyFactory
 {
     /**
      * The memory amount needed to store a string was obtained empirically from this data:.
@@ -47,23 +50,29 @@ class CachingStrategyFactory
      */
     public const MAX_NUM_STRINGS_PER_TEMP_FILE = 10000;
 
+    private MemoryLimit $memoryLimit;
+
+    public function __construct(MemoryLimit $memoryLimit)
+    {
+        $this->memoryLimit = $memoryLimit;
+    }
+
     /**
      * Returns the best caching strategy, given the number of unique shared strings
      * and the amount of memory available.
      *
-     * @param null|int      $sharedStringsUniqueCount Number of unique shared strings (NULL if unknown)
-     * @param string        $tempFolder               Temporary folder where the temporary files to store shared strings will be stored
-     * @param HelperFactory $helperFactory            Factory to create helpers
+     * @param null|int $sharedStringsUniqueCount Number of unique shared strings (NULL if unknown)
+     * @param string   $tempFolder               Temporary folder where the temporary files to store shared strings will be stored
      *
      * @return CachingStrategyInterface The best caching strategy
      */
-    public function createBestCachingStrategy($sharedStringsUniqueCount, $tempFolder, $helperFactory)
+    public function createBestCachingStrategy(?int $sharedStringsUniqueCount, string $tempFolder): CachingStrategyInterface
     {
         if ($this->isInMemoryStrategyUsageSafe($sharedStringsUniqueCount)) {
             return new InMemoryStrategy($sharedStringsUniqueCount);
         }
 
-        return new FileBasedStrategy($tempFolder, self::MAX_NUM_STRINGS_PER_TEMP_FILE, $helperFactory);
+        return new FileBasedStrategy($tempFolder, self::MAX_NUM_STRINGS_PER_TEMP_FILE);
     }
 
     /**
@@ -71,17 +80,15 @@ class CachingStrategyFactory
      * and the amount of memory available.
      *
      * @param null|int $sharedStringsUniqueCount Number of unique shared strings (NULL if unknown)
-     *
-     * @return bool
      */
-    protected function isInMemoryStrategyUsageSafe($sharedStringsUniqueCount)
+    private function isInMemoryStrategyUsageSafe(?int $sharedStringsUniqueCount): bool
     {
         // if the number of shared strings in unknown, do not use "in memory" strategy
         if (null === $sharedStringsUniqueCount) {
             return false;
         }
 
-        $memoryAvailable = $this->getMemoryLimitInKB();
+        $memoryAvailable = $this->memoryLimit->getMemoryLimitInKB();
 
         if (-1 === (int) $memoryAvailable) {
             // if cannot get memory limit or if memory limit set as unlimited, don't trust and play safe
@@ -93,49 +100,4 @@ class CachingStrategyFactory
 
         return $isInMemoryStrategyUsageSafe;
     }
-
-    /**
-     * Returns the PHP "memory_limit" in Kilobytes.
-     *
-     * @return float
-     */
-    protected function getMemoryLimitInKB()
-    {
-        $memoryLimitFormatted = $this->getMemoryLimitFromIni();
-        $memoryLimitFormatted = strtolower(trim($memoryLimitFormatted));
-
-        // No memory limit
-        if ('-1' === $memoryLimitFormatted) {
-            return -1;
-        }
-
-        if (preg_match('/(\d+)([bkmgt])b?/', $memoryLimitFormatted, $matches)) {
-            $amount = (int) ($matches[1]);
-            $unit = $matches[2];
-
-            switch ($unit) {
-                case 'b': return $amount / 1024;
-
-                case 'k': return $amount;
-
-                case 'm': return $amount * 1024;
-
-                case 'g': return $amount * 1024 * 1024;
-
-                case 't': return $amount * 1024 * 1024 * 1024;
-            }
-        }
-
-        return -1;
-    }
-
-    /**
-     * Returns the formatted "memory_limit" value.
-     *
-     * @return string
-     */
-    protected function getMemoryLimitFromIni()
-    {
-        return ini_get('memory_limit');
-    }
 }
diff --git a/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/CachingStrategyInterface.php b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/CachingStrategyInterface.php
index b3148274e3a..e120c9595a8 100644
--- a/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/CachingStrategyInterface.php
+++ b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/CachingStrategyInterface.php
@@ -1,9 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX\Manager\SharedStringsCaching;
 
 /**
- * Interface CachingStrategyInterface.
+ * @internal
  */
 interface CachingStrategyInterface
 {
@@ -13,27 +15,27 @@ interface CachingStrategyInterface
      * @param string $sharedString      The string to be added to the cache
      * @param int    $sharedStringIndex Index of the shared string in the sharedStrings.xml file
      */
-    public function addStringForIndex($sharedString, $sharedStringIndex);
+    public function addStringForIndex(string $sharedString, int $sharedStringIndex): void;
 
     /**
      * Closes the cache after the last shared string was added.
      * This prevents any additional string from being added to the cache.
      */
-    public function closeCache();
+    public function closeCache(): void;
 
     /**
      * Returns the string located at the given index from the cache.
      *
      * @param int $sharedStringIndex Index of the shared string in the sharedStrings.xml file
      *
-     * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If no shared string found for the given index
-     *
      * @return string The shared string at the given index
+     *
+     * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If no shared string found for the given index
      */
-    public function getStringAtIndex($sharedStringIndex);
+    public function getStringAtIndex(int $sharedStringIndex): string;
 
     /**
      * Destroys the cache, freeing memory and removing any created artifacts.
      */
-    public function clearCache();
+    public function clearCache(): void;
 }
diff --git a/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/FileBasedStrategy.php b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/FileBasedStrategy.php
index 8b19e525925..b17a6754526 100644
--- a/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/FileBasedStrategy.php
+++ b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/FileBasedStrategy.php
@@ -1,66 +1,67 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX\Manager\SharedStringsCaching;
 
+use OpenSpout\Common\Helper\FileSystemHelper;
 use OpenSpout\Reader\Exception\SharedStringNotFoundException;
-use OpenSpout\Reader\XLSX\Creator\HelperFactory;
 
 /**
  * This class implements the file-based caching strategy for shared strings.
  * Shared strings are stored in small files (with a max number of strings per file).
  * This strategy is slower than an in-memory strategy but is used to avoid out of memory crashes.
+ *
+ * @internal
  */
-class FileBasedStrategy implements CachingStrategyInterface
+final class FileBasedStrategy implements CachingStrategyInterface
 {
-    /** Value to use to escape the line feed character ("\n") */
+    /**
+     * Value to use to escape the line feed character ("\n").
+     */
     public const ESCAPED_LINE_FEED_CHARACTER = '_x000A_';
 
-    /** @var \OpenSpout\Common\Helper\GlobalFunctionsHelper Helper to work with global functions */
-    protected $globalFunctionsHelper;
-
-    /** @var \OpenSpout\Common\Helper\FileSystemHelper Helper to perform file system operations */
-    protected $fileSystemHelper;
+    /** @var FileSystemHelper Helper to perform file system operations */
+    private FileSystemHelper $fileSystemHelper;
 
     /** @var string Temporary folder where the temporary files will be created */
-    protected $tempFolder;
+    private string $tempFolder;
 
     /**
      * @var int Maximum number of strings that can be stored in one temp file
      *
      * @see CachingStrategyFactory::MAX_NUM_STRINGS_PER_TEMP_FILE
      */
-    protected $maxNumStringsPerTempFile;
+    private int $maxNumStringsPerTempFile;
 
     /** @var null|resource Pointer to the last temp file a shared string was written to */
-    protected $tempFilePointer;
+    private $tempFilePointer;
 
     /**
      * @var string Path of the temporary file whose contents is currently stored in memory
      *
      * @see CachingStrategyFactory::MAX_NUM_STRINGS_PER_TEMP_FILE
      */
-    protected $inMemoryTempFilePath;
+    private string $inMemoryTempFilePath = '';
 
     /**
-     * @var array Contents of the temporary file that was last read
-     *
      * @see CachingStrategyFactory::MAX_NUM_STRINGS_PER_TEMP_FILE
+     *
+     * @var string[] Contents of the temporary file that was last read
      */
-    protected $inMemoryTempFileContents;
+    private array $inMemoryTempFileContents;
 
     /**
-     * @param string        $tempFolder               Temporary folder where the temporary files to store shared strings will be stored
-     * @param int           $maxNumStringsPerTempFile Maximum number of strings that can be stored in one temp file
-     * @param HelperFactory $helperFactory            Factory to create helpers
+     * @param string $tempFolder               Temporary folder where the temporary files to store shared strings will be stored
+     * @param int    $maxNumStringsPerTempFile Maximum number of strings that can be stored in one temp file
      */
-    public function __construct($tempFolder, $maxNumStringsPerTempFile, $helperFactory)
+    public function __construct(string $tempFolder, int $maxNumStringsPerTempFile)
     {
-        $this->fileSystemHelper = $helperFactory->createFileSystemHelper($tempFolder);
+        $this->fileSystemHelper = new FileSystemHelper($tempFolder);
         $this->tempFolder = $this->fileSystemHelper->createFolder($tempFolder, uniqid('sharedstrings'));
 
         $this->maxNumStringsPerTempFile = $maxNumStringsPerTempFile;
 
-        $this->globalFunctionsHelper = $helperFactory->createGlobalFunctionsHelper();
         $this->tempFilePointer = null;
     }
 
@@ -70,33 +71,35 @@ class FileBasedStrategy implements CachingStrategyInterface
      * @param string $sharedString      The string to be added to the cache
      * @param int    $sharedStringIndex Index of the shared string in the sharedStrings.xml file
      */
-    public function addStringForIndex($sharedString, $sharedStringIndex)
+    public function addStringForIndex(string $sharedString, int $sharedStringIndex): void
     {
         $tempFilePath = $this->getSharedStringTempFilePath($sharedStringIndex);
 
-        if (!$this->globalFunctionsHelper->file_exists($tempFilePath)) {
-            if ($this->tempFilePointer) {
-                $this->globalFunctionsHelper->fclose($this->tempFilePointer);
+        if (!file_exists($tempFilePath)) {
+            if (null !== $this->tempFilePointer) {
+                fclose($this->tempFilePointer);
             }
-            $this->tempFilePointer = $this->globalFunctionsHelper->fopen($tempFilePath, 'w');
+            $resource = fopen($tempFilePath, 'w');
+            \assert(false !== $resource);
+            $this->tempFilePointer = $resource;
         }
 
         // The shared string retrieval logic expects each cell data to be on one line only
         // Encoding the line feed character allows to preserve this assumption
         $lineFeedEncodedSharedString = $this->escapeLineFeed($sharedString);
 
-        $this->globalFunctionsHelper->fwrite($this->tempFilePointer, $lineFeedEncodedSharedString.PHP_EOL);
+        fwrite($this->tempFilePointer, $lineFeedEncodedSharedString.PHP_EOL);
     }
 
     /**
      * Closes the cache after the last shared string was added.
      * This prevents any additional string from being added to the cache.
      */
-    public function closeCache()
+    public function closeCache(): void
     {
         // close pointer to the last temp file that was written
-        if ($this->tempFilePointer) {
-            $this->globalFunctionsHelper->fclose($this->tempFilePointer);
+        if (null !== $this->tempFilePointer) {
+            fclose($this->tempFilePointer);
         }
     }
 
@@ -105,21 +108,25 @@ class FileBasedStrategy implements CachingStrategyInterface
      *
      * @param int $sharedStringIndex Index of the shared string in the sharedStrings.xml file
      *
-     * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If no shared string found for the given index
-     *
      * @return string The shared string at the given index
+     *
+     * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If no shared string found for the given index
      */
-    public function getStringAtIndex($sharedStringIndex)
+    public function getStringAtIndex(int $sharedStringIndex): string
     {
         $tempFilePath = $this->getSharedStringTempFilePath($sharedStringIndex);
         $indexInFile = $sharedStringIndex % $this->maxNumStringsPerTempFile;
 
-        if (!$this->globalFunctionsHelper->file_exists($tempFilePath)) {
+        if (!file_exists($tempFilePath)) {
             throw new SharedStringNotFoundException("Shared string temp file not found: {$tempFilePath} ; for index: {$sharedStringIndex}");
         }
 
         if ($this->inMemoryTempFilePath !== $tempFilePath) {
-            $this->inMemoryTempFileContents = explode(PHP_EOL, $this->globalFunctionsHelper->file_get_contents($tempFilePath));
+            $tempFilePath = realpath($tempFilePath);
+            \assert(false !== $tempFilePath);
+            $contents = file_get_contents($tempFilePath);
+            \assert(false !== $contents);
+            $this->inMemoryTempFileContents = explode(PHP_EOL, $contents);
             $this->inMemoryTempFilePath = $tempFilePath;
         }
 
@@ -141,11 +148,9 @@ class FileBasedStrategy implements CachingStrategyInterface
     /**
      * Destroys the cache, freeing memory and removing any created artifacts.
      */
-    public function clearCache()
+    public function clearCache(): void
     {
-        if ($this->tempFolder) {
-            $this->fileSystemHelper->deleteFolderRecursively($this->tempFolder);
-        }
+        $this->fileSystemHelper->deleteFolderRecursively($this->tempFolder);
     }
 
     /**
@@ -155,7 +160,7 @@ class FileBasedStrategy implements CachingStrategyInterface
      *
      * @return string The temp file path for the given index
      */
-    protected function getSharedStringTempFilePath($sharedStringIndex)
+    private function getSharedStringTempFilePath(int $sharedStringIndex): string
     {
         $numTempFile = (int) ($sharedStringIndex / $this->maxNumStringsPerTempFile);
 
@@ -164,24 +169,16 @@ class FileBasedStrategy implements CachingStrategyInterface
 
     /**
      * Escapes the line feed characters (\n).
-     *
-     * @param string $unescapedString
-     *
-     * @return string
      */
-    private function escapeLineFeed($unescapedString)
+    private function escapeLineFeed(string $unescapedString): string
     {
         return str_replace("\n", self::ESCAPED_LINE_FEED_CHARACTER, $unescapedString);
     }
 
     /**
      * Unescapes the line feed characters (\n).
-     *
-     * @param string $escapedString
-     *
-     * @return string
      */
-    private function unescapeLineFeed($escapedString)
+    private function unescapeLineFeed(string $escapedString): string
     {
         return str_replace(self::ESCAPED_LINE_FEED_CHARACTER, "\n", $escapedString);
     }
diff --git a/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/InMemoryStrategy.php b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/InMemoryStrategy.php
index 04312ad21f5..48858101664 100644
--- a/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/InMemoryStrategy.php
+++ b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/InMemoryStrategy.php
@@ -1,27 +1,33 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX\Manager\SharedStringsCaching;
 
 use OpenSpout\Reader\Exception\SharedStringNotFoundException;
+use RuntimeException;
+use SplFixedArray;
 
 /**
  * This class implements the in-memory caching strategy for shared strings.
  * This strategy is used when the number of unique strings is low, compared to the memory available.
+ *
+ * @internal
  */
-class InMemoryStrategy implements CachingStrategyInterface
+final class InMemoryStrategy implements CachingStrategyInterface
 {
-    /** @var \SplFixedArray Array used to cache the shared strings */
-    protected $inMemoryCache;
+    /** @var SplFixedArray<string> Array used to cache the shared strings */
+    private SplFixedArray $inMemoryCache;
 
     /** @var bool Whether the cache has been closed */
-    protected $isCacheClosed;
+    private bool $isCacheClosed;
 
     /**
      * @param int $sharedStringsUniqueCount Number of unique shared strings
      */
-    public function __construct($sharedStringsUniqueCount)
+    public function __construct(int $sharedStringsUniqueCount)
     {
-        $this->inMemoryCache = new \SplFixedArray($sharedStringsUniqueCount);
+        $this->inMemoryCache = new SplFixedArray($sharedStringsUniqueCount);
         $this->isCacheClosed = false;
     }
 
@@ -31,7 +37,7 @@ class InMemoryStrategy implements CachingStrategyInterface
      * @param string $sharedString      The string to be added to the cache
      * @param int    $sharedStringIndex Index of the shared string in the sharedStrings.xml file
      */
-    public function addStringForIndex($sharedString, $sharedStringIndex)
+    public function addStringForIndex(string $sharedString, int $sharedStringIndex): void
     {
         if (!$this->isCacheClosed) {
             $this->inMemoryCache->offsetSet($sharedStringIndex, $sharedString);
@@ -42,7 +48,7 @@ class InMemoryStrategy implements CachingStrategyInterface
      * Closes the cache after the last shared string was added.
      * This prevents any additional string from being added to the cache.
      */
-    public function closeCache()
+    public function closeCache(): void
     {
         $this->isCacheClosed = true;
     }
@@ -52,15 +58,15 @@ class InMemoryStrategy implements CachingStrategyInterface
      *
      * @param int $sharedStringIndex Index of the shared string in the sharedStrings.xml file
      *
-     * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If no shared string found for the given index
-     *
      * @return string The shared string at the given index
+     *
+     * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If no shared string found for the given index
      */
-    public function getStringAtIndex($sharedStringIndex)
+    public function getStringAtIndex(int $sharedStringIndex): string
     {
         try {
             return $this->inMemoryCache->offsetGet($sharedStringIndex);
-        } catch (\RuntimeException $e) {
+        } catch (RuntimeException $e) {
             throw new SharedStringNotFoundException("Shared string not found for index: {$sharedStringIndex}");
         }
     }
@@ -68,9 +74,9 @@ class InMemoryStrategy implements CachingStrategyInterface
     /**
      * Destroys the cache, freeing memory and removing any created artifacts.
      */
-    public function clearCache()
+    public function clearCache(): void
     {
-        $this->inMemoryCache = new \SplFixedArray(0);
+        $this->inMemoryCache = new SplFixedArray(0);
         $this->isCacheClosed = false;
     }
 }
diff --git a/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/MemoryLimit.php b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/MemoryLimit.php
new file mode 100644
index 00000000000..e9d76286c5e
--- /dev/null
+++ b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsCaching/MemoryLimit.php
@@ -0,0 +1,50 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Reader\XLSX\Manager\SharedStringsCaching;
+
+/**
+ * @internal
+ */
+final class MemoryLimit
+{
+    private string $memoryLimit;
+
+    public function __construct(string $memoryLimit)
+    {
+        $this->memoryLimit = $memoryLimit;
+    }
+
+    /**
+     * Returns the PHP "memory_limit" in Kilobytes.
+     */
+    public function getMemoryLimitInKB(): float
+    {
+        $memoryLimitFormatted = strtolower(trim($this->memoryLimit));
+
+        // No memory limit
+        if ('-1' === $memoryLimitFormatted) {
+            return -1;
+        }
+
+        if (1 === preg_match('/(\d+)([bkmgt])b?/', $memoryLimitFormatted, $matches)) {
+            $amount = (int) $matches[1];
+            $unit = $matches[2];
+
+            switch ($unit) {
+                case 'b': return $amount / 1024;
+
+                case 'k': return $amount;
+
+                case 'm': return $amount * 1024;
+
+                case 'g': return $amount * 1024 * 1024;
+
+                case 't': return $amount * 1024 * 1024 * 1024;
+            }
+        }
+
+        return -1;
+    }
+}
diff --git a/lib/openspout/src/Reader/XLSX/Manager/SharedStringsManager.php b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsManager.php
index 120ce6871c3..499559c8470 100644
--- a/lib/openspout/src/Reader/XLSX/Manager/SharedStringsManager.php
+++ b/lib/openspout/src/Reader/XLSX/Manager/SharedStringsManager.php
@@ -1,83 +1,68 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX\Manager;
 
+use DOMElement;
 use OpenSpout\Common\Exception\IOException;
 use OpenSpout\Reader\Exception\XMLProcessingException;
 use OpenSpout\Reader\Wrapper\XMLReader;
-use OpenSpout\Reader\XLSX\Creator\HelperFactory;
-use OpenSpout\Reader\XLSX\Creator\InternalEntityFactory;
 use OpenSpout\Reader\XLSX\Manager\SharedStringsCaching\CachingStrategyFactory;
 use OpenSpout\Reader\XLSX\Manager\SharedStringsCaching\CachingStrategyInterface;
+use OpenSpout\Reader\XLSX\Options;
 
 /**
- * This class manages the shared strings defined in the associated XML file.
+ * @internal
  */
-class SharedStringsManager
+final class SharedStringsManager
 {
-    /** Definition of XML nodes names used to parse data */
+    /**
+     * Definition of XML nodes names used to parse data.
+     */
     public const XML_NODE_SST = 'sst';
     public const XML_NODE_SI = 'si';
     public const XML_NODE_R = 'r';
     public const XML_NODE_T = 't';
 
-    /** Definition of XML attributes used to parse data */
+    /**
+     * Definition of XML attributes used to parse data.
+     */
     public const XML_ATTRIBUTE_COUNT = 'count';
     public const XML_ATTRIBUTE_UNIQUE_COUNT = 'uniqueCount';
     public const XML_ATTRIBUTE_XML_SPACE = 'xml:space';
     public const XML_ATTRIBUTE_VALUE_PRESERVE = 'preserve';
 
     /** @var string Path of the XLSX file being read */
-    protected $filePath;
+    private string $filePath;
 
-    /** @var string Temporary folder where the temporary files to store shared strings will be stored */
-    protected $tempFolder;
+    private Options $options;
 
     /** @var WorkbookRelationshipsManager Helps retrieving workbook relationships */
-    protected $workbookRelationshipsManager;
-
-    /** @var InternalEntityFactory Factory to create entities */
-    protected $entityFactory;
-
-    /** @var HelperFactory Factory to create helpers */
-    protected $helperFactory;
+    private WorkbookRelationshipsManager $workbookRelationshipsManager;
 
     /** @var CachingStrategyFactory Factory to create shared strings caching strategies */
-    protected $cachingStrategyFactory;
+    private CachingStrategyFactory $cachingStrategyFactory;
 
     /** @var CachingStrategyInterface The best caching strategy for storing shared strings */
-    protected $cachingStrategy;
+    private CachingStrategyInterface $cachingStrategy;
 
-    /**
-     * @param string                       $filePath                     Path of the XLSX file being read
-     * @param string                       $tempFolder                   Temporary folder where the temporary files to store shared strings will be stored
-     * @param WorkbookRelationshipsManager $workbookRelationshipsManager Helps retrieving workbook relationships
-     * @param InternalEntityFactory        $entityFactory                Factory to create entities
-     * @param HelperFactory                $helperFactory                Factory to create helpers
-     * @param CachingStrategyFactory       $cachingStrategyFactory       Factory to create shared strings caching strategies
-     */
     public function __construct(
-        $filePath,
-        $tempFolder,
-        $workbookRelationshipsManager,
-        $entityFactory,
-        $helperFactory,
-        $cachingStrategyFactory
+        string $filePath,
+        Options $options,
+        WorkbookRelationshipsManager $workbookRelationshipsManager,
+        CachingStrategyFactory $cachingStrategyFactory
     ) {
         $this->filePath = $filePath;
-        $this->tempFolder = $tempFolder;
+        $this->options = $options;
         $this->workbookRelationshipsManager = $workbookRelationshipsManager;
-        $this->entityFactory = $entityFactory;
-        $this->helperFactory = $helperFactory;
         $this->cachingStrategyFactory = $cachingStrategyFactory;
     }
 
     /**
      * Returns whether the XLSX file contains a shared strings XML file.
-     *
-     * @return bool
      */
-    public function hasSharedStrings()
+    public function hasSharedStrings(): bool
     {
         return $this->workbookRelationshipsManager->hasSharedStringsXMLFile();
     }
@@ -94,10 +79,10 @@ class SharedStringsManager
      *
      * @throws \OpenSpout\Common\Exception\IOException If shared strings XML file can't be read
      */
-    public function extractSharedStrings()
+    public function extractSharedStrings(): void
     {
         $sharedStringsXMLFilePath = $this->workbookRelationshipsManager->getSharedStringsXMLFilePath();
-        $xmlReader = $this->entityFactory->createXMLReader();
+        $xmlReader = new XMLReader();
         $sharedStringIndex = 0;
 
         if (false === $xmlReader->openFileInZip($this->filePath, $sharedStringsXMLFilePath)) {
@@ -131,11 +116,11 @@ class SharedStringsManager
      *
      * @param int $sharedStringIndex Index of the shared string in the sharedStrings.xml file
      *
-     * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If no shared string found for the given index
-     *
      * @return string The shared string at the given index
+     *
+     * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If no shared string found for the given index
      */
-    public function getStringAtIndex($sharedStringIndex)
+    public function getStringAtIndex(int $sharedStringIndex): string
     {
         return $this->cachingStrategy->getStringAtIndex($sharedStringIndex);
     }
@@ -143,9 +128,9 @@ class SharedStringsManager
     /**
      * Destroys the cache, freeing memory and removing any created artifacts.
      */
-    public function cleanup()
+    public function cleanup(): void
     {
-        if (null !== $this->cachingStrategy) {
+        if (isset($this->cachingStrategy)) {
             $this->cachingStrategy->clearCache();
         }
     }
@@ -153,13 +138,13 @@ class SharedStringsManager
     /**
      * Returns the shared strings unique count, as specified in <sst> tag.
      *
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XMLReader instance
-     *
-     * @throws \OpenSpout\Common\Exception\IOException If sharedStrings.xml is invalid and can't be read
+     * @param XMLReader $xmlReader XMLReader instance
      *
      * @return null|int Number of unique shared strings in the sharedStrings.xml file
+     *
+     * @throws \OpenSpout\Common\Exception\IOException If sharedStrings.xml is invalid and can't be read
      */
-    protected function getSharedStringsUniqueCount($xmlReader)
+    private function getSharedStringsUniqueCount(XMLReader $xmlReader): ?int
     {
         $xmlReader->next(self::XML_NODE_SST);
 
@@ -183,37 +168,39 @@ class SharedStringsManager
      * Returns the best shared strings caching strategy.
      *
      * @param null|int $sharedStringsUniqueCount Number of unique shared strings (NULL if unknown)
-     *
-     * @return CachingStrategyInterface
      */
-    protected function getBestSharedStringsCachingStrategy($sharedStringsUniqueCount)
+    private function getBestSharedStringsCachingStrategy(?int $sharedStringsUniqueCount): CachingStrategyInterface
     {
         return $this->cachingStrategyFactory
-            ->createBestCachingStrategy($sharedStringsUniqueCount, $this->tempFolder, $this->helperFactory)
+            ->createBestCachingStrategy($sharedStringsUniqueCount, $this->options->getTempFolder())
         ;
     }
 
     /**
      * Processes the shared strings item XML node which the given XML reader is positioned on.
      *
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader         XML Reader positioned on a "<si>" node
-     * @param int                                 $sharedStringIndex Index of the processed shared strings item
+     * @param XMLReader $xmlReader         XML Reader positioned on a "<si>" node
+     * @param int       $sharedStringIndex Index of the processed shared strings item
      */
-    protected function processSharedStringsItem($xmlReader, $sharedStringIndex)
+    private function processSharedStringsItem(XMLReader $xmlReader, int $sharedStringIndex): void
     {
         $sharedStringValue = '';
 
         // NOTE: expand() will automatically decode all XML entities of the child nodes
-        /** @var \DOMElement $siNode */
         $siNode = $xmlReader->expand();
+        \assert($siNode instanceof DOMElement);
         $textNodes = $siNode->getElementsByTagName(self::XML_NODE_T);
 
         foreach ($textNodes as $textNode) {
             if ($this->shouldExtractTextNodeValue($textNode)) {
                 $textNodeValue = $textNode->nodeValue;
+                \assert(null !== $textNodeValue);
                 $shouldPreserveWhitespace = $this->shouldPreserveWhitespace($textNode);
 
-                $sharedStringValue .= ($shouldPreserveWhitespace) ? $textNodeValue : trim($textNodeValue);
+                $sharedStringValue .= $shouldPreserveWhitespace
+                    ? $textNodeValue
+                    : trim($textNodeValue)
+                ;
             }
         }
 
@@ -225,13 +212,15 @@ class SharedStringsManager
      * Some text nodes are part of a node describing the pronunciation for instance.
      * We'll only consider the nodes whose parents are "<si>" or "<r>".
      *
-     * @param \DOMElement $textNode Text node to check
+     * @param DOMElement $textNode Text node to check
      *
      * @return bool Whether the given text node's value must be extracted
      */
-    protected function shouldExtractTextNodeValue($textNode)
+    private function shouldExtractTextNodeValue(DOMElement $textNode): bool
     {
-        $parentTagName = $textNode->parentNode->localName;
+        $parentNode = $textNode->parentNode;
+        \assert(null !== $parentNode);
+        $parentTagName = $parentNode->localName;
 
         return self::XML_NODE_SI === $parentTagName || self::XML_NODE_R === $parentTagName;
     }
@@ -239,11 +228,11 @@ class SharedStringsManager
     /**
      * If the text node has the attribute 'xml:space="preserve"', then preserve whitespace.
      *
-     * @param \DOMElement $textNode The text node element (<t>) whose whitespace may be preserved
+     * @param DOMElement $textNode The text node element (<t>) whose whitespace may be preserved
      *
      * @return bool Whether whitespace should be preserved
      */
-    protected function shouldPreserveWhitespace($textNode)
+    private function shouldPreserveWhitespace(DOMElement $textNode): bool
     {
         $spaceValue = $textNode->getAttribute(self::XML_ATTRIBUTE_XML_SPACE);
 
diff --git a/lib/openspout/src/Reader/XLSX/Manager/SheetManager.php b/lib/openspout/src/Reader/XLSX/Manager/SheetManager.php
index e2e173e87b1..296cba3f371 100644
--- a/lib/openspout/src/Reader/XLSX/Manager/SheetManager.php
+++ b/lib/openspout/src/Reader/XLSX/Manager/SheetManager.php
@@ -1,29 +1,42 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX\Manager;
 
-use OpenSpout\Reader\Common\Entity\Options;
+use OpenSpout\Common\Helper\Escaper\XLSX;
+use OpenSpout\Reader\Common\Manager\RowManager;
 use OpenSpout\Reader\Common\XMLProcessor;
-use OpenSpout\Reader\XLSX\Creator\InternalEntityFactory;
+use OpenSpout\Reader\Wrapper\XMLReader;
+use OpenSpout\Reader\XLSX\Helper\CellValueFormatter;
+use OpenSpout\Reader\XLSX\Options;
+use OpenSpout\Reader\XLSX\RowIterator;
 use OpenSpout\Reader\XLSX\Sheet;
+use OpenSpout\Reader\XLSX\SheetHeaderReader;
 
 /**
- * This class manages XLSX sheets.
+ * @internal
  */
-class SheetManager
+final class SheetManager
 {
-    /** Paths of XML files relative to the XLSX file root */
+    /**
+     * Paths of XML files relative to the XLSX file root.
+     */
     public const WORKBOOK_XML_RELS_FILE_PATH = 'xl/_rels/workbook.xml.rels';
     public const WORKBOOK_XML_FILE_PATH = 'xl/workbook.xml';
 
-    /** Definition of XML node names used to parse data */
+    /**
+     * Definition of XML node names used to parse data.
+     */
     public const XML_NODE_WORKBOOK_PROPERTIES = 'workbookPr';
     public const XML_NODE_WORKBOOK_VIEW = 'workbookView';
     public const XML_NODE_SHEET = 'sheet';
     public const XML_NODE_SHEETS = 'sheets';
     public const XML_NODE_RELATIONSHIP = 'Relationship';
 
-    /** Definition of XML attributes used to parse data */
+    /**
+     * Definition of XML attributes used to parse data.
+     */
     public const XML_ATTRIBUTE_DATE_1904 = 'date1904';
     public const XML_ATTRIBUTE_ACTIVE_TAB = 'activeTab';
     public const XML_ATTRIBUTE_R_ID = 'r:id';
@@ -32,51 +45,41 @@ class SheetManager
     public const XML_ATTRIBUTE_ID = 'Id';
     public const XML_ATTRIBUTE_TARGET = 'Target';
 
-    /** State value to represent a hidden sheet */
+    /**
+     * State value to represent a hidden sheet.
+     */
     public const SHEET_STATE_HIDDEN = 'hidden';
 
     /** @var string Path of the XLSX file being read */
-    protected $filePath;
+    private string $filePath;
 
-    /** @var \OpenSpout\Common\Manager\OptionsManagerInterface Reader's options manager */
-    protected $optionsManager;
+    private Options $options;
 
-    /** @var \OpenSpout\Reader\XLSX\Manager\SharedStringsManager Manages shared strings */
-    protected $sharedStringsManager;
+    /** @var SharedStringsManager Manages shared strings */
+    private SharedStringsManager $sharedStringsManager;
 
-    /** @var \OpenSpout\Common\Helper\GlobalFunctionsHelper Helper to work with global functions */
-    protected $globalFunctionsHelper;
+    /** @var XLSX Used to unescape XML data */
+    private XLSX $escaper;
 
-    /** @var InternalEntityFactory Factory to create entities */
-    protected $entityFactory;
-
-    /** @var \OpenSpout\Common\Helper\Escaper\XLSX Used to unescape XML data */
-    protected $escaper;
-
-    /** @var array List of sheets */
-    protected $sheets;
+    /** @var Sheet[] List of sheets */
+    private array $sheets;
 
     /** @var int Index of the sheet currently read */
-    protected $currentSheetIndex;
+    private int $currentSheetIndex;
 
     /** @var int Index of the active sheet (0 by default) */
-    protected $activeSheetIndex;
+    private int $activeSheetIndex;
 
-    /**
-     * @param string                                              $filePath             Path of the XLSX file being read
-     * @param \OpenSpout\Common\Manager\OptionsManagerInterface   $optionsManager       Reader's options manager
-     * @param \OpenSpout\Reader\XLSX\Manager\SharedStringsManager $sharedStringsManager Manages shared strings
-     * @param \OpenSpout\Common\Helper\Escaper\XLSX               $escaper              Used to unescape XML data
-     * @param InternalEntityFactory                               $entityFactory        Factory to create entities
-     * @param mixed                                               $sharedStringsManager
-     */
-    public function __construct($filePath, $optionsManager, $sharedStringsManager, $escaper, $entityFactory)
-    {
+    public function __construct(
+        string $filePath,
+        Options $options,
+        SharedStringsManager $sharedStringsManager,
+        XLSX $escaper
+    ) {
         $this->filePath = $filePath;
-        $this->optionsManager = $optionsManager;
+        $this->options = $options;
         $this->sharedStringsManager = $sharedStringsManager;
         $this->escaper = $escaper;
-        $this->entityFactory = $entityFactory;
     }
 
     /**
@@ -85,14 +88,14 @@ class SheetManager
      *
      * @return Sheet[] Sheets within the XLSX file
      */
-    public function getSheets()
+    public function getSheets(): array
     {
         $this->sheets = [];
         $this->currentSheetIndex = 0;
         $this->activeSheetIndex = 0; // By default, the first sheet is active
 
-        $xmlReader = $this->entityFactory->createXMLReader();
-        $xmlProcessor = $this->entityFactory->createXMLProcessor($xmlReader);
+        $xmlReader = new XMLReader();
+        $xmlProcessor = new XMLProcessor($xmlReader);
 
         $xmlProcessor->registerCallback(self::XML_NODE_WORKBOOK_PROPERTIES, XMLProcessor::NODE_TYPE_START, [$this, 'processWorkbookPropertiesStartingNode']);
         $xmlProcessor->registerCallback(self::XML_NODE_WORKBOOK_VIEW, XMLProcessor::NODE_TYPE_START, [$this, 'processWorkbookViewStartingNode']);
@@ -112,12 +115,12 @@ class SheetManager
      *
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processWorkbookPropertiesStartingNode($xmlReader)
+    private function processWorkbookPropertiesStartingNode(XMLReader $xmlReader): int
     {
         // Using "filter_var($x, FILTER_VALIDATE_BOOLEAN)" here because the value of the "date1904" attribute
         // may be the string "false", that is not mapped to the boolean "false" by default...
         $shouldUse1904Dates = filter_var($xmlReader->getAttribute(self::XML_ATTRIBUTE_DATE_1904), FILTER_VALIDATE_BOOLEAN);
-        $this->optionsManager->setOption(Options::SHOULD_USE_1904_DATES, $shouldUse1904Dates);
+        $this->options->SHOULD_USE_1904_DATES = $shouldUse1904Dates;
 
         return XMLProcessor::PROCESSING_CONTINUE;
     }
@@ -127,7 +130,7 @@ class SheetManager
      *
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processWorkbookViewStartingNode($xmlReader)
+    private function processWorkbookViewStartingNode(XMLReader $xmlReader): int
     {
         // The "workbookView" node is located before "sheet" nodes, ensuring that
         // the active sheet is known before parsing sheets data.
@@ -141,7 +144,7 @@ class SheetManager
      *
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processSheetStartingNode($xmlReader)
+    private function processSheetStartingNode(XMLReader $xmlReader): int
     {
         $isSheetActive = ($this->currentSheetIndex === $this->activeSheetIndex);
         $this->sheets[] = $this->getSheetFromSheetXMLNode($xmlReader, $this->currentSheetIndex, $isSheetActive);
@@ -153,7 +156,7 @@ class SheetManager
     /**
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processSheetsEndingNode()
+    private function processSheetsEndingNode(): int
     {
         return XMLProcessor::PROCESSING_STOP;
     }
@@ -169,27 +172,27 @@ class SheetManager
      *
      * @return \OpenSpout\Reader\XLSX\Sheet Sheet instance
      */
-    protected function getSheetFromSheetXMLNode($xmlReaderOnSheetNode, $sheetIndexZeroBased, $isSheetActive)
+    private function getSheetFromSheetXMLNode(XMLReader $xmlReaderOnSheetNode, int $sheetIndexZeroBased, bool $isSheetActive): Sheet
     {
         $sheetId = $xmlReaderOnSheetNode->getAttribute(self::XML_ATTRIBUTE_R_ID);
+        \assert(null !== $sheetId);
 
         $sheetState = $xmlReaderOnSheetNode->getAttribute(self::XML_ATTRIBUTE_STATE);
         $isSheetVisible = (self::SHEET_STATE_HIDDEN !== $sheetState);
 
         $escapedSheetName = $xmlReaderOnSheetNode->getAttribute(self::XML_ATTRIBUTE_NAME);
+        \assert(null !== $escapedSheetName);
         $sheetName = $this->escaper->unescape($escapedSheetName);
 
         $sheetDataXMLFilePath = $this->getSheetDataXMLFilePathForSheetId($sheetId);
 
-        return $this->entityFactory->createSheet(
-            $this->filePath,
-            $sheetDataXMLFilePath,
+        return new Sheet(
+            $this->createRowIterator($this->filePath, $sheetDataXMLFilePath, $this->options, $this->sharedStringsManager),
+            $this->createSheetHeaderReader($this->filePath, $sheetDataXMLFilePath),
             $sheetIndexZeroBased,
             $sheetName,
             $isSheetActive,
-            $isSheetVisible,
-            $this->optionsManager,
-            $this->sharedStringsManager
+            $isSheetVisible
         );
     }
 
@@ -198,12 +201,12 @@ class SheetManager
      *
      * @return string The XML file path describing the sheet inside "workbook.xml.res", for the given sheet ID
      */
-    protected function getSheetDataXMLFilePathForSheetId($sheetId)
+    private function getSheetDataXMLFilePathForSheetId(string $sheetId): string
     {
         $sheetDataXMLFilePath = '';
 
         // find the file path of the sheet, by looking at the "workbook.xml.res" file
-        $xmlReader = $this->entityFactory->createXMLReader();
+        $xmlReader = new XMLReader();
         if ($xmlReader->openFileInZip($this->filePath, self::WORKBOOK_XML_RELS_FILE_PATH)) {
             while ($xmlReader->read()) {
                 if ($xmlReader->isPositionedOnStartingNode(self::XML_NODE_RELATIONSHIP)) {
@@ -213,9 +216,10 @@ class SheetManager
                         // In workbook.xml.rels, it is only "worksheets/sheet1.xml"
                         // In [Content_Types].xml, the path is "/xl/worksheets/sheet1.xml"
                         $sheetDataXMLFilePath = $xmlReader->getAttribute(self::XML_ATTRIBUTE_TARGET);
+                        \assert(null !== $sheetDataXMLFilePath);
 
                         // sometimes, the sheet data file path already contains "/xl/"...
-                        if (0 !== strpos($sheetDataXMLFilePath, '/xl/')) {
+                        if (!str_starts_with($sheetDataXMLFilePath, '/xl/')) {
                             $sheetDataXMLFilePath = '/xl/'.$sheetDataXMLFilePath;
 
                             break;
@@ -229,4 +233,53 @@ class SheetManager
 
         return $sheetDataXMLFilePath;
     }
+
+    private function createRowIterator(
+        string $filePath,
+        string $sheetDataXMLFilePath,
+        Options $options,
+        SharedStringsManager $sharedStringsManager
+    ): RowIterator {
+        $xmlReader = new XMLReader();
+
+        $workbookRelationshipsManager = new WorkbookRelationshipsManager($filePath);
+        $styleManager = new StyleManager(
+            $filePath,
+            $workbookRelationshipsManager->hasStylesXMLFile()
+                ? $workbookRelationshipsManager->getStylesXMLFilePath()
+                : null
+        );
+
+        $cellValueFormatter = new CellValueFormatter(
+            $sharedStringsManager,
+            $styleManager,
+            $options->SHOULD_FORMAT_DATES,
+            $options->SHOULD_USE_1904_DATES,
+            new XLSX()
+        );
+
+        return new RowIterator(
+            $filePath,
+            $sheetDataXMLFilePath,
+            $options->SHOULD_PRESERVE_EMPTY_ROWS,
+            $xmlReader,
+            new XMLProcessor($xmlReader),
+            $cellValueFormatter,
+            new RowManager()
+        );
+    }
+
+    private function createSheetHeaderReader(
+        string $filePath,
+        string $sheetDataXMLFilePath
+    ): SheetHeaderReader {
+        $xmlReader = new XMLReader();
+
+        return new SheetHeaderReader(
+            $filePath,
+            $sheetDataXMLFilePath,
+            $xmlReader,
+            new XMLProcessor($xmlReader)
+        );
+    }
 }
diff --git a/lib/openspout/src/Reader/XLSX/Manager/StyleManager.php b/lib/openspout/src/Reader/XLSX/Manager/StyleManager.php
index 4eb90468bb0..6c56ea8f781 100644
--- a/lib/openspout/src/Reader/XLSX/Manager/StyleManager.php
+++ b/lib/openspout/src/Reader/XLSX/Manager/StyleManager.php
@@ -1,36 +1,42 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX\Manager;
 
-use OpenSpout\Reader\XLSX\Creator\InternalEntityFactory;
+use OpenSpout\Reader\Wrapper\XMLReader;
 
-/**
- * This class manages XLSX styles.
- */
-class StyleManager
+class StyleManager implements StyleManagerInterface
 {
-    /** Nodes used to find relevant information in the styles XML file */
+    /**
+     * Nodes used to find relevant information in the styles XML file.
+     */
     public const XML_NODE_NUM_FMTS = 'numFmts';
     public const XML_NODE_NUM_FMT = 'numFmt';
     public const XML_NODE_CELL_XFS = 'cellXfs';
     public const XML_NODE_XF = 'xf';
 
-    /** Attributes used to find relevant information in the styles XML file */
+    /**
+     * Attributes used to find relevant information in the styles XML file.
+     */
     public const XML_ATTRIBUTE_NUM_FMT_ID = 'numFmtId';
     public const XML_ATTRIBUTE_FORMAT_CODE = 'formatCode';
     public const XML_ATTRIBUTE_APPLY_NUMBER_FORMAT = 'applyNumberFormat';
+    public const XML_ATTRIBUTE_COUNT = 'count';
 
-    /** By convention, default style ID is 0 */
+    /**
+     * By convention, default style ID is 0.
+     */
     public const DEFAULT_STYLE_ID = 0;
 
     public const NUMBER_FORMAT_GENERAL = 'General';
 
     /**
-     * @see https://msdn.microsoft.com/en-us/library/ff529597(v=office.12).aspx
+     * Mapping between built-in numFmtId and the associated format - for dates only.
      *
-     * @var array Mapping between built-in numFmtId and the associated format - for dates only
+     * @see https://msdn.microsoft.com/en-us/library/ff529597(v=office.12).aspx
      */
-    protected static $builtinNumFmtIdToNumFormatMapping = [
+    private const builtinNumFmtIdToNumFormatMapping = [
         14 => 'm/d/yyyy', // @NOTE: ECMA spec is 'mm-dd-yy'
         15 => 'd-mmm-yy',
         16 => 'd-mmm',
@@ -46,56 +52,33 @@ class StyleManager
     ];
 
     /** @var string Path of the XLSX file being read */
-    protected $filePath;
-
-    /** @var bool Whether the XLSX file contains a styles XML file */
-    protected $hasStylesXMLFile;
+    private string $filePath;
 
     /** @var null|string Path of the styles XML file */
-    protected $stylesXMLFilePath;
+    private ?string $stylesXMLFilePath;
 
-    /** @var InternalEntityFactory Factory to create entities */
-    protected $entityFactory;
+    /** @var array<int, string> Array containing a mapping NUM_FMT_ID => FORMAT_CODE */
+    private array $customNumberFormats;
 
-    /** @var array Array containing the IDs of built-in number formats indicating a date */
-    protected $builtinNumFmtIdIndicatingDates;
+    /** @var array<array-key, array<string, null|bool|int>> Array containing a mapping STYLE_ID => [STYLE_ATTRIBUTES] */
+    private array $stylesAttributes;
 
-    /** @var null|array Array containing a mapping NUM_FMT_ID => FORMAT_CODE */
-    protected $customNumberFormats;
-
-    /** @var null|array Array containing a mapping STYLE_ID => [STYLE_ATTRIBUTES] */
-    protected $stylesAttributes;
-
-    /** @var array Cache containing a mapping NUM_FMT_ID => IS_DATE_FORMAT. Used to avoid lots of recalculations */
-    protected $numFmtIdToIsDateFormatCache = [];
+    /** @var array<int, bool> Cache containing a mapping NUM_FMT_ID => IS_DATE_FORMAT. Used to avoid lots of recalculations */
+    private array $numFmtIdToIsDateFormatCache = [];
 
     /**
-     * @param string                       $filePath                     Path of the XLSX file being read
-     * @param WorkbookRelationshipsManager $workbookRelationshipsManager Helps retrieving workbook relationships
-     * @param InternalEntityFactory        $entityFactory                Factory to create entities
+     * @param string  $filePath          Path of the XLSX file being read
+     * @param ?string $stylesXMLFilePath
      */
-    public function __construct($filePath, $workbookRelationshipsManager, $entityFactory)
+    public function __construct(string $filePath, ?string $stylesXMLFilePath)
     {
         $this->filePath = $filePath;
-        $this->entityFactory = $entityFactory;
-        $this->builtinNumFmtIdIndicatingDates = array_keys(self::$builtinNumFmtIdToNumFormatMapping);
-        $this->hasStylesXMLFile = $workbookRelationshipsManager->hasStylesXMLFile();
-        if ($this->hasStylesXMLFile) {
-            $this->stylesXMLFilePath = $workbookRelationshipsManager->getStylesXMLFilePath();
-        }
+        $this->stylesXMLFilePath = $stylesXMLFilePath;
     }
 
-    /**
-     * Returns whether the style with the given ID should consider
-     * numeric values as timestamps and format the cell as a date.
-     *
-     * @param int $styleId Zero-based style ID
-     *
-     * @return bool Whether the cell with the given cell should display a date instead of a numeric value
-     */
-    public function shouldFormatNumericValueAsDate($styleId)
+    public function shouldFormatNumericValueAsDate(int $styleId): bool
     {
-        if (!$this->hasStylesXMLFile) {
+        if (null === $this->stylesXMLFilePath) {
             return false;
         }
 
@@ -113,22 +96,15 @@ class StyleManager
         return $this->doesStyleIndicateDate($styleAttributes);
     }
 
-    /**
-     * Returns the format as defined in "styles.xml" of the given style.
-     * NOTE: It is assumed that the style DOES have a number format associated to it.
-     *
-     * @param int $styleId Zero-based style ID
-     *
-     * @return string The number format code associated with the given style
-     */
-    public function getNumberFormatCode($styleId)
+    public function getNumberFormatCode(int $styleId): string
     {
         $stylesAttributes = $this->getStylesAttributes();
         $styleAttributes = $stylesAttributes[$styleId];
         $numFmtId = $styleAttributes[self::XML_ATTRIBUTE_NUM_FMT_ID];
+        \assert(\is_int($numFmtId));
 
         if ($this->isNumFmtIdBuiltInDateFormat($numFmtId)) {
-            $numberFormatCode = self::$builtinNumFmtIdToNumFormatMapping[$numFmtId];
+            $numberFormatCode = self::builtinNumFmtIdToNumFormatMapping[$numFmtId];
         } else {
             $customNumberFormats = $this->getCustomNumberFormats();
             $numberFormatCode = $customNumberFormats[$numFmtId];
@@ -137,19 +113,44 @@ class StyleManager
         return $numberFormatCode;
     }
 
+    /**
+     * @return array<int, string> The custom number formats
+     */
+    protected function getCustomNumberFormats(): array
+    {
+        if (!isset($this->customNumberFormats)) {
+            $this->extractRelevantInfo();
+        }
+
+        return $this->customNumberFormats;
+    }
+
+    /**
+     * @return array<array-key, array<string, null|bool|int>> The styles attributes
+     */
+    protected function getStylesAttributes(): array
+    {
+        if (!isset($this->stylesAttributes)) {
+            $this->extractRelevantInfo();
+        }
+
+        return $this->stylesAttributes;
+    }
+
     /**
      * Reads the styles.xml file and extract the relevant information from the file.
      */
-    protected function extractRelevantInfo()
+    private function extractRelevantInfo(): void
     {
         $this->customNumberFormats = [];
         $this->stylesAttributes = [];
 
-        $xmlReader = $this->entityFactory->createXMLReader();
+        $xmlReader = new XMLReader();
 
         if ($xmlReader->openFileInZip($this->filePath, $this->stylesXMLFilePath)) {
             while ($xmlReader->read()) {
-                if ($xmlReader->isPositionedOnStartingNode(self::XML_NODE_NUM_FMTS)) {
+                if ($xmlReader->isPositionedOnStartingNode(self::XML_NODE_NUM_FMTS)
+                    && '0' !== $xmlReader->getAttribute(self::XML_ATTRIBUTE_COUNT)) {
                     $this->extractNumberFormats($xmlReader);
                 } elseif ($xmlReader->isPositionedOnStartingNode(self::XML_NODE_CELL_XFS)) {
                     $this->extractStyleAttributes($xmlReader);
@@ -167,12 +168,13 @@ class StyleManager
      *
      * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XML Reader positioned on the "numFmts" node
      */
-    protected function extractNumberFormats($xmlReader)
+    private function extractNumberFormats(XMLReader $xmlReader): void
     {
         while ($xmlReader->read()) {
             if ($xmlReader->isPositionedOnStartingNode(self::XML_NODE_NUM_FMT)) {
-                $numFmtId = (int) ($xmlReader->getAttribute(self::XML_ATTRIBUTE_NUM_FMT_ID));
+                $numFmtId = (int) $xmlReader->getAttribute(self::XML_ATTRIBUTE_NUM_FMT_ID);
                 $formatCode = $xmlReader->getAttribute(self::XML_ATTRIBUTE_FORMAT_CODE);
+                \assert(null !== $formatCode);
                 $this->customNumberFormats[$numFmtId] = $formatCode;
             } elseif ($xmlReader->isPositionedOnEndingNode(self::XML_NODE_NUM_FMTS)) {
                 // Once done reading "numFmts" node's children
@@ -188,7 +190,7 @@ class StyleManager
      *
      * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XML Reader positioned on the "cellXfs" node
      */
-    protected function extractStyleAttributes($xmlReader)
+    private function extractStyleAttributes(XMLReader $xmlReader): void
     {
         while ($xmlReader->read()) {
             if ($xmlReader->isPositionedOnStartingNode(self::XML_NODE_XF)) {
@@ -210,35 +212,11 @@ class StyleManager
     }
 
     /**
-     * @return array The custom number formats
-     */
-    protected function getCustomNumberFormats()
-    {
-        if (!isset($this->customNumberFormats)) {
-            $this->extractRelevantInfo();
-        }
-
-        return $this->customNumberFormats;
-    }
-
-    /**
-     * @return array The styles attributes
-     */
-    protected function getStylesAttributes()
-    {
-        if (!isset($this->stylesAttributes)) {
-            $this->extractRelevantInfo();
-        }
-
-        return $this->stylesAttributes;
-    }
-
-    /**
-     * @param array $styleAttributes Array containing the style attributes (2 keys: "applyNumberFormat" and "numFmtId")
+     * @param array<string, null|bool|int> $styleAttributes Array containing the style attributes (2 keys: "applyNumberFormat" and "numFmtId")
      *
      * @return bool Whether the style with the given attributes indicates that the number is a date
      */
-    protected function doesStyleIndicateDate($styleAttributes)
+    private function doesStyleIndicateDate(array $styleAttributes): bool
     {
         $applyNumberFormat = $styleAttributes[self::XML_ATTRIBUTE_APPLY_NUMBER_FORMAT];
         $numFmtId = $styleAttributes[self::XML_ATTRIBUTE_NUM_FMT_ID];
@@ -248,7 +226,7 @@ class StyleManager
         //  - "numFmtId" attribute set
         // This is a preliminary check, as having "numFmtId" set just means the style should apply a specific number format,
         // but this is not necessarily a date.
-        if (false === $applyNumberFormat || null === $numFmtId) {
+        if (false === $applyNumberFormat || !\is_int($numFmtId)) {
             return false;
         }
 
@@ -260,11 +238,9 @@ class StyleManager
      * The result is cached to avoid recomputing the same thing over and over, as
      * "numFmtId" attributes can be shared between multiple styles.
      *
-     * @param int $numFmtId
-     *
      * @return bool Whether the number format ID indicates that the number is a date
      */
-    protected function doesNumFmtIdIndicateDate($numFmtId)
+    private function doesNumFmtIdIndicateDate(int $numFmtId): bool
     {
         if (!isset($this->numFmtIdToIsDateFormatCache[$numFmtId])) {
             $formatCode = $this->getFormatCodeForNumFmtId($numFmtId);
@@ -279,11 +255,9 @@ class StyleManager
     }
 
     /**
-     * @param int $numFmtId
-     *
      * @return null|string The custom number format or NULL if none defined for the given numFmtId
      */
-    protected function getFormatCodeForNumFmtId($numFmtId)
+    private function getFormatCodeForNumFmtId(int $numFmtId): ?string
     {
         $customNumberFormats = $this->getCustomNumberFormats();
 
@@ -292,21 +266,17 @@ class StyleManager
     }
 
     /**
-     * @param int $numFmtId
-     *
      * @return bool Whether the number format ID indicates that the number is a date
      */
-    protected function isNumFmtIdBuiltInDateFormat($numFmtId)
+    private function isNumFmtIdBuiltInDateFormat(int $numFmtId): bool
     {
-        return \in_array($numFmtId, $this->builtinNumFmtIdIndicatingDates, true);
+        return \array_key_exists($numFmtId, self::builtinNumFmtIdToNumFormatMapping);
     }
 
     /**
-     * @param null|string $formatCode
-     *
      * @return bool Whether the given format code indicates that the number is a date
      */
-    protected function isFormatCodeCustomDateFormat($formatCode)
+    private function isFormatCodeCustomDateFormat(?string $formatCode): bool
     {
         // if no associated format code or if using the default "General" format
         if (null === $formatCode || 0 === strcasecmp($formatCode, self::NUMBER_FORMAT_GENERAL)) {
@@ -317,15 +287,14 @@ class StyleManager
     }
 
     /**
-     * @param string $formatCode
-     *
      * @return bool Whether the given format code matches a date format pattern
      */
-    protected function isFormatCodeMatchingDateFormatPattern($formatCode)
+    private function isFormatCodeMatchingDateFormatPattern(string $formatCode): bool
     {
         // Remove extra formatting (what's between [ ], the brackets should not be preceded by a "\")
         $pattern = '((?<!\\\)\[.+?(?<!\\\)\])';
         $formatCode = preg_replace($pattern, '', $formatCode);
+        \assert(null !== $formatCode);
 
         // custom date formats contain specific characters to represent the date:
         // e - yy - m - d - h - s
@@ -337,7 +306,7 @@ class StyleManager
             // character not preceded by "\" (case insensitive)
             $pattern = '/(?<!\\\)'.$dateFormatCharacter.'/i';
 
-            if (preg_match($pattern, $formatCode)) {
+            if (1 === preg_match($pattern, $formatCode)) {
                 $hasFoundDateFormatCharacter = true;
 
                 break;
diff --git a/lib/openspout/src/Reader/XLSX/Manager/StyleManagerInterface.php b/lib/openspout/src/Reader/XLSX/Manager/StyleManagerInterface.php
new file mode 100644
index 00000000000..3999d0b1194
--- /dev/null
+++ b/lib/openspout/src/Reader/XLSX/Manager/StyleManagerInterface.php
@@ -0,0 +1,31 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Reader\XLSX\Manager;
+
+/**
+ * @internal
+ */
+interface StyleManagerInterface
+{
+    /**
+     * Returns whether the style with the given ID should consider
+     * numeric values as timestamps and format the cell as a date.
+     *
+     * @param int $styleId Zero-based style ID
+     *
+     * @return bool Whether the cell with the given cell should display a date instead of a numeric value
+     */
+    public function shouldFormatNumericValueAsDate(int $styleId): bool;
+
+    /**
+     * Returns the format as defined in "styles.xml" of the given style.
+     * NOTE: It is assumed that the style DOES have a number format associated to it.
+     *
+     * @param int $styleId Zero-based style ID
+     *
+     * @return string The number format code associated with the given style
+     */
+    public function getNumberFormatCode(int $styleId): string;
+}
diff --git a/lib/openspout/src/Reader/XLSX/Manager/WorkbookRelationshipsManager.php b/lib/openspout/src/Reader/XLSX/Manager/WorkbookRelationshipsManager.php
index 721ed724501..1c3e209ce32 100644
--- a/lib/openspout/src/Reader/XLSX/Manager/WorkbookRelationshipsManager.php
+++ b/lib/openspout/src/Reader/XLSX/Manager/WorkbookRelationshipsManager.php
@@ -1,62 +1,64 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX\Manager;
 
 use OpenSpout\Common\Exception\IOException;
 use OpenSpout\Reader\Wrapper\XMLReader;
-use OpenSpout\Reader\XLSX\Creator\InternalEntityFactory;
 
 /**
- * This class manages the workbook relationships defined in the associated XML file.
+ * @internal
  */
-class WorkbookRelationshipsManager
+final class WorkbookRelationshipsManager
 {
     public const BASE_PATH = 'xl/';
 
-    /** Path of workbook relationships XML file inside the XLSX file */
+    /**
+     * Path of workbook relationships XML file inside the XLSX file.
+     */
     public const WORKBOOK_RELS_XML_FILE_PATH = 'xl/_rels/workbook.xml.rels';
 
-    /** Relationships types - For Transitional and Strict OOXML */
+    /**
+     * Relationships types - For Transitional and Strict OOXML.
+     */
     public const RELATIONSHIP_TYPE_SHARED_STRINGS = 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/sharedStrings';
     public const RELATIONSHIP_TYPE_STYLES = 'http://schemas.openxmlformats.org/officeDocument/2006/relationships/styles';
     public const RELATIONSHIP_TYPE_SHARED_STRINGS_STRICT = 'http://purl.oclc.org/ooxml/officeDocument/relationships/sharedStrings';
     public const RELATIONSHIP_TYPE_STYLES_STRICT = 'http://purl.oclc.org/ooxml/officeDocument/relationships/styles';
 
-    /** Nodes and attributes used to find relevant information in the workbook relationships XML file */
+    /**
+     * Nodes and attributes used to find relevant information in the workbook relationships XML file.
+     */
     public const XML_NODE_RELATIONSHIP = 'Relationship';
     public const XML_ATTRIBUTE_TYPE = 'Type';
     public const XML_ATTRIBUTE_TARGET = 'Target';
 
     /** @var string Path of the XLSX file being read */
-    private $filePath;
+    private string $filePath;
 
-    /** @var InternalEntityFactory Factory to create entities */
-    private $entityFactory;
-
-    /** @var null|array Cache of the already read workbook relationships: [TYPE] => [FILE_NAME] */
-    private $cachedWorkbookRelationships;
+    /** @var array<string, string> Cache of the already read workbook relationships: [TYPE] => [FILE_NAME] */
+    private array $cachedWorkbookRelationships;
 
     /**
-     * @param string                $filePath      Path of the XLSX file being read
-     * @param InternalEntityFactory $entityFactory Factory to create entities
+     * @param string $filePath Path of the XLSX file being read
      */
-    public function __construct($filePath, $entityFactory)
+    public function __construct(string $filePath)
     {
         $this->filePath = $filePath;
-        $this->entityFactory = $entityFactory;
     }
 
     /**
      * @return string The path of the shared string XML file
      */
-    public function getSharedStringsXMLFilePath()
+    public function getSharedStringsXMLFilePath(): string
     {
         $workbookRelationships = $this->getWorkbookRelationships();
         $sharedStringsXMLFilePath = $workbookRelationships[self::RELATIONSHIP_TYPE_SHARED_STRINGS]
             ?? $workbookRelationships[self::RELATIONSHIP_TYPE_SHARED_STRINGS_STRICT];
 
         // the file path can be relative (e.g. "styles.xml") or absolute (e.g. "/xl/styles.xml")
-        $doesContainBasePath = (false !== strpos($sharedStringsXMLFilePath, self::BASE_PATH));
+        $doesContainBasePath = str_contains($sharedStringsXMLFilePath, self::BASE_PATH);
         if (!$doesContainBasePath) {
             // make sure we return an absolute file path
             $sharedStringsXMLFilePath = self::BASE_PATH.$sharedStringsXMLFilePath;
@@ -68,7 +70,7 @@ class WorkbookRelationshipsManager
     /**
      * @return bool Whether the XLSX file contains a shared string XML file
      */
-    public function hasSharedStringsXMLFile()
+    public function hasSharedStringsXMLFile(): bool
     {
         $workbookRelationships = $this->getWorkbookRelationships();
 
@@ -79,7 +81,7 @@ class WorkbookRelationshipsManager
     /**
      * @return bool Whether the XLSX file contains a styles XML file
      */
-    public function hasStylesXMLFile()
+    public function hasStylesXMLFile(): bool
     {
         $workbookRelationships = $this->getWorkbookRelationships();
 
@@ -90,14 +92,14 @@ class WorkbookRelationshipsManager
     /**
      * @return string The path of the styles XML file
      */
-    public function getStylesXMLFilePath()
+    public function getStylesXMLFilePath(): string
     {
         $workbookRelationships = $this->getWorkbookRelationships();
         $stylesXMLFilePath = $workbookRelationships[self::RELATIONSHIP_TYPE_STYLES]
             ?? $workbookRelationships[self::RELATIONSHIP_TYPE_STYLES_STRICT];
 
         // the file path can be relative (e.g. "styles.xml") or absolute (e.g. "/xl/styles.xml")
-        $doesContainBasePath = (false !== strpos($stylesXMLFilePath, self::BASE_PATH));
+        $doesContainBasePath = str_contains($stylesXMLFilePath, self::BASE_PATH);
         if (!$doesContainBasePath) {
             // make sure we return a full path
             $stylesXMLFilePath = self::BASE_PATH.$stylesXMLFilePath;
@@ -110,14 +112,14 @@ class WorkbookRelationshipsManager
      * Reads the workbook.xml.rels and extracts the filename associated to the different types.
      * It caches the result so that the file is read only once.
      *
-     * @throws \OpenSpout\Common\Exception\IOException If workbook.xml.rels can't be read
+     * @return array<string, string>
      *
-     * @return array
+     * @throws \OpenSpout\Common\Exception\IOException If workbook.xml.rels can't be read
      */
-    private function getWorkbookRelationships()
+    private function getWorkbookRelationships(): array
     {
         if (!isset($this->cachedWorkbookRelationships)) {
-            $xmlReader = $this->entityFactory->createXMLReader();
+            $xmlReader = new XMLReader();
 
             if (false === $xmlReader->openFileInZip($this->filePath, self::WORKBOOK_RELS_XML_FILE_PATH)) {
                 throw new IOException('Could not open "'.self::WORKBOOK_RELS_XML_FILE_PATH.'".');
@@ -135,13 +137,12 @@ class WorkbookRelationshipsManager
 
     /**
      * Extracts and store the data of the current workbook relationship.
-     *
-     * @param XMLReader $xmlReader
      */
-    private function processWorkbookRelationship($xmlReader)
+    private function processWorkbookRelationship(XMLReader $xmlReader): void
     {
         $type = $xmlReader->getAttribute(self::XML_ATTRIBUTE_TYPE);
         $target = $xmlReader->getAttribute(self::XML_ATTRIBUTE_TARGET);
+        \assert(null !== $target);
 
         // @NOTE: if a type is defined more than once, we overwrite the previous value
         // To be changed if we want to get the file paths of sheet XML files for instance.
diff --git a/lib/openspout/src/Reader/XLSX/Options.php b/lib/openspout/src/Reader/XLSX/Options.php
new file mode 100644
index 00000000000..1c8331f827a
--- /dev/null
+++ b/lib/openspout/src/Reader/XLSX/Options.php
@@ -0,0 +1,16 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Reader\XLSX;
+
+use OpenSpout\Common\TempFolderOptionTrait;
+
+final class Options
+{
+    use TempFolderOptionTrait;
+
+    public bool $SHOULD_FORMAT_DATES = false;
+    public bool $SHOULD_PRESERVE_EMPTY_ROWS = false;
+    public bool $SHOULD_USE_1904_DATES = false;
+}
diff --git a/lib/openspout/src/Reader/XLSX/Reader.php b/lib/openspout/src/Reader/XLSX/Reader.php
index 197c7fc58d0..f08df2f000f 100644
--- a/lib/openspout/src/Reader/XLSX/Reader.php
+++ b/lib/openspout/src/Reader/XLSX/Reader.php
@@ -1,61 +1,61 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX;
 
 use OpenSpout\Common\Exception\IOException;
-use OpenSpout\Common\Helper\GlobalFunctionsHelper;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Reader\Common\Creator\InternalEntityFactoryInterface;
-use OpenSpout\Reader\Common\Entity\Options;
-use OpenSpout\Reader\ReaderAbstract;
-use OpenSpout\Reader\XLSX\Creator\InternalEntityFactory;
-use OpenSpout\Reader\XLSX\Creator\ManagerFactory;
+use OpenSpout\Common\Helper\Escaper\XLSX;
+use OpenSpout\Reader\AbstractReader;
+use OpenSpout\Reader\XLSX\Manager\SharedStringsCaching\CachingStrategyFactory;
+use OpenSpout\Reader\XLSX\Manager\SharedStringsCaching\MemoryLimit;
+use OpenSpout\Reader\XLSX\Manager\SharedStringsManager;
+use OpenSpout\Reader\XLSX\Manager\SheetManager;
+use OpenSpout\Reader\XLSX\Manager\WorkbookRelationshipsManager;
+use ZipArchive;
 
 /**
- * This class provides support to read data from a XLSX file.
+ * @extends AbstractReader<SheetIterator>
  */
-class Reader extends ReaderAbstract
+final class Reader extends AbstractReader
 {
-    /** @var ManagerFactory */
-    protected $managerFactory;
+    private ZipArchive $zip;
 
-    /** @var \ZipArchive */
-    protected $zip;
-
-    /** @var \OpenSpout\Reader\XLSX\Manager\SharedStringsManager Manages shared strings */
-    protected $sharedStringsManager;
+    /** @var SharedStringsManager Manages shared strings */
+    private SharedStringsManager $sharedStringsManager;
 
     /** @var SheetIterator To iterator over the XLSX sheets */
-    protected $sheetIterator;
+    private SheetIterator $sheetIterator;
+
+    private Options $options;
+    private CachingStrategyFactory $cachingStrategyFactory;
 
     public function __construct(
-        OptionsManagerInterface $optionsManager,
-        GlobalFunctionsHelper $globalFunctionsHelper,
-        InternalEntityFactoryInterface $entityFactory,
-        ManagerFactory $managerFactory
+        ?Options $options = null,
+        ?CachingStrategyFactory $cachingStrategyFactory = null
     ) {
-        parent::__construct($optionsManager, $globalFunctionsHelper, $entityFactory);
-        $this->managerFactory = $managerFactory;
+        $this->options = $options ?? new Options();
+
+        if (null === $cachingStrategyFactory) {
+            $memoryLimit = \ini_get('memory_limit');
+            \assert(false !== $memoryLimit);
+
+            $cachingStrategyFactory = new CachingStrategyFactory(new MemoryLimit($memoryLimit));
+        }
+        $this->cachingStrategyFactory = $cachingStrategyFactory;
     }
 
-    /**
-     * @param string $tempFolder Temporary folder where the temporary files will be created
-     *
-     * @return Reader
-     */
-    public function setTempFolder($tempFolder)
+    public function getSheetIterator(): SheetIterator
     {
-        $this->optionsManager->setOption(Options::TEMP_FOLDER, $tempFolder);
+        $this->ensureStreamOpened();
 
-        return $this;
+        return $this->sheetIterator;
     }
 
     /**
      * Returns whether stream wrappers are supported.
-     *
-     * @return bool
      */
-    protected function doesSupportStreamWrapper()
+    protected function doesSupportStreamWrapper(): bool
     {
         return false;
     }
@@ -70,53 +70,42 @@ class Reader extends ReaderAbstract
      * @throws \OpenSpout\Common\Exception\IOException            If the file at the given path or its content cannot be read
      * @throws \OpenSpout\Reader\Exception\NoSheetsFoundException If there are no sheets in the file
      */
-    protected function openReader($filePath)
+    protected function openReader(string $filePath): void
     {
-        /** @var InternalEntityFactory $entityFactory */
-        $entityFactory = $this->entityFactory;
+        $this->zip = new ZipArchive();
 
-        $this->zip = $entityFactory->createZipArchive();
-
-        if (true === $this->zip->open($filePath)) {
-            $tempFolder = $this->optionsManager->getOption(Options::TEMP_FOLDER);
-            $this->sharedStringsManager = $this->managerFactory->createSharedStringsManager($filePath, $tempFolder, $entityFactory);
-
-            if ($this->sharedStringsManager->hasSharedStrings()) {
-                // Extracts all the strings from the sheets for easy access in the future
-                $this->sharedStringsManager->extractSharedStrings();
-            }
-
-            $this->sheetIterator = $entityFactory->createSheetIterator(
-                $filePath,
-                $this->optionsManager,
-                $this->sharedStringsManager
-            );
-        } else {
+        if (true !== $this->zip->open($filePath)) {
             throw new IOException("Could not open {$filePath} for reading.");
         }
-    }
 
-    /**
-     * Returns an iterator to iterate over sheets.
-     *
-     * @return SheetIterator To iterate over sheets
-     */
-    protected function getConcreteSheetIterator()
-    {
-        return $this->sheetIterator;
+        $this->sharedStringsManager = new SharedStringsManager(
+            $filePath,
+            $this->options,
+            new WorkbookRelationshipsManager($filePath),
+            $this->cachingStrategyFactory
+        );
+
+        if ($this->sharedStringsManager->hasSharedStrings()) {
+            // Extracts all the strings from the sheets for easy access in the future
+            $this->sharedStringsManager->extractSharedStrings();
+        }
+
+        $this->sheetIterator = new SheetIterator(
+            new SheetManager(
+                $filePath,
+                $this->options,
+                $this->sharedStringsManager,
+                new XLSX()
+            )
+        );
     }
 
     /**
      * Closes the reader. To be used after reading the file.
      */
-    protected function closeReader()
+    protected function closeReader(): void
     {
-        if (null !== $this->zip) {
-            $this->zip->close();
-        }
-
-        if (null !== $this->sharedStringsManager) {
-            $this->sharedStringsManager->cleanup();
-        }
+        $this->zip->close();
+        $this->sharedStringsManager->cleanup();
     }
 }
diff --git a/lib/openspout/src/Reader/XLSX/RowIterator.php b/lib/openspout/src/Reader/XLSX/RowIterator.php
index de383706629..e1c7d2d920c 100644
--- a/lib/openspout/src/Reader/XLSX/RowIterator.php
+++ b/lib/openspout/src/Reader/XLSX/RowIterator.php
@@ -1,105 +1,105 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX;
 
+use DOMElement;
 use OpenSpout\Common\Entity\Cell;
 use OpenSpout\Common\Entity\Row;
 use OpenSpout\Common\Exception\IOException;
 use OpenSpout\Reader\Common\Manager\RowManager;
 use OpenSpout\Reader\Common\XMLProcessor;
 use OpenSpout\Reader\Exception\InvalidValueException;
-use OpenSpout\Reader\Exception\XMLProcessingException;
-use OpenSpout\Reader\IteratorInterface;
+use OpenSpout\Reader\RowIteratorInterface;
 use OpenSpout\Reader\Wrapper\XMLReader;
-use OpenSpout\Reader\XLSX\Creator\InternalEntityFactory;
 use OpenSpout\Reader\XLSX\Helper\CellHelper;
 use OpenSpout\Reader\XLSX\Helper\CellValueFormatter;
 
-class RowIterator implements IteratorInterface
+final class RowIterator implements RowIteratorInterface
 {
-    /** Definition of XML nodes names used to parse data */
+    /**
+     * Definition of XML nodes names used to parse data.
+     */
     public const XML_NODE_DIMENSION = 'dimension';
     public const XML_NODE_WORKSHEET = 'worksheet';
     public const XML_NODE_ROW = 'row';
     public const XML_NODE_CELL = 'c';
 
-    /** Definition of XML attributes used to parse data */
+    /**
+     * Definition of XML attributes used to parse data.
+     */
     public const XML_ATTRIBUTE_REF = 'ref';
     public const XML_ATTRIBUTE_SPANS = 'spans';
     public const XML_ATTRIBUTE_ROW_INDEX = 'r';
     public const XML_ATTRIBUTE_CELL_INDEX = 'r';
 
     /** @var string Path of the XLSX file being read */
-    protected $filePath;
+    private string $filePath;
 
     /** @var string Path of the sheet data XML file as in [Content_Types].xml */
-    protected $sheetDataXMLFilePath;
+    private string $sheetDataXMLFilePath;
 
-    /** @var \OpenSpout\Reader\Wrapper\XMLReader The XMLReader object that will help read sheet's XML data */
-    protected $xmlReader;
+    /** @var XMLReader The XMLReader object that will help read sheet's XML data */
+    private XMLReader $xmlReader;
 
-    /** @var \OpenSpout\Reader\Common\XMLProcessor Helper Object to process XML nodes */
-    protected $xmlProcessor;
+    /** @var XMLProcessor Helper Object to process XML nodes */
+    private XMLProcessor $xmlProcessor;
 
     /** @var Helper\CellValueFormatter Helper to format cell values */
-    protected $cellValueFormatter;
+    private Helper\CellValueFormatter $cellValueFormatter;
 
-    /** @var \OpenSpout\Reader\Common\Manager\RowManager Manages rows */
-    protected $rowManager;
-
-    /** @var \OpenSpout\Reader\XLSX\Creator\InternalEntityFactory Factory to create entities */
-    protected $entityFactory;
+    /** @var RowManager Manages rows */
+    private RowManager $rowManager;
 
     /**
      * TODO: This variable can be deleted when row indices get preserved.
      *
      * @var int Number of read rows
      */
-    protected $numReadRows = 0;
+    private int $numReadRows = 0;
 
     /** @var Row Contains the row currently processed */
-    protected $currentlyProcessedRow;
+    private Row $currentlyProcessedRow;
 
     /** @var null|Row Buffer used to store the current row, while checking if there are more rows to read */
-    protected $rowBuffer;
+    private ?Row $rowBuffer;
 
     /** @var bool Indicates whether all rows have been read */
-    protected $hasReachedEndOfFile = false;
+    private bool $hasReachedEndOfFile = false;
 
     /** @var int The number of columns the sheet has (0 meaning undefined) */
-    protected $numColumns = 0;
+    private int $numColumns = 0;
 
     /** @var bool Whether empty rows should be returned or skipped */
-    protected $shouldPreserveEmptyRows;
+    private bool $shouldPreserveEmptyRows;
 
     /** @var int Last row index processed (one-based) */
-    protected $lastRowIndexProcessed = 0;
+    private int $lastRowIndexProcessed = 0;
 
     /** @var int Row index to be processed next (one-based) */
-    protected $nextRowIndexToBeProcessed = 0;
+    private int $nextRowIndexToBeProcessed = 0;
 
     /** @var int Last column index processed (zero-based) */
-    protected $lastColumnIndexProcessed = -1;
+    private int $lastColumnIndexProcessed = -1;
 
     /**
-     * @param string                $filePath                Path of the XLSX file being read
-     * @param string                $sheetDataXMLFilePath    Path of the sheet data XML file as in [Content_Types].xml
-     * @param bool                  $shouldPreserveEmptyRows Whether empty rows should be preserved
-     * @param XMLReader             $xmlReader               XML Reader
-     * @param XMLProcessor          $xmlProcessor            Helper to process XML files
-     * @param CellValueFormatter    $cellValueFormatter      Helper to format cell values
-     * @param RowManager            $rowManager              Manages rows
-     * @param InternalEntityFactory $entityFactory           Factory to create entities
+     * @param string             $filePath                Path of the XLSX file being read
+     * @param string             $sheetDataXMLFilePath    Path of the sheet data XML file as in [Content_Types].xml
+     * @param bool               $shouldPreserveEmptyRows Whether empty rows should be preserved
+     * @param XMLReader          $xmlReader               XML Reader
+     * @param XMLProcessor       $xmlProcessor            Helper to process XML files
+     * @param CellValueFormatter $cellValueFormatter      Helper to format cell values
+     * @param RowManager         $rowManager              Manages rows
      */
     public function __construct(
-        $filePath,
-        $sheetDataXMLFilePath,
-        $shouldPreserveEmptyRows,
-        $xmlReader,
+        string $filePath,
+        string $sheetDataXMLFilePath,
+        bool $shouldPreserveEmptyRows,
+        XMLReader $xmlReader,
         XMLProcessor $xmlProcessor,
         CellValueFormatter $cellValueFormatter,
-        RowManager $rowManager,
-        InternalEntityFactory $entityFactory
+        RowManager $rowManager
     ) {
         $this->filePath = $filePath;
         $this->sheetDataXMLFilePath = $this->normalizeSheetDataXMLFilePath($sheetDataXMLFilePath);
@@ -107,7 +107,6 @@ class RowIterator implements IteratorInterface
         $this->xmlReader = $xmlReader;
         $this->cellValueFormatter = $cellValueFormatter;
         $this->rowManager = $rowManager;
-        $this->entityFactory = $entityFactory;
 
         // Register all callbacks to process different nodes when reading the XML file
         $this->xmlProcessor = $xmlProcessor;
@@ -127,7 +126,6 @@ class RowIterator implements IteratorInterface
      *
      * @throws \OpenSpout\Common\Exception\IOException If the sheet data XML cannot be read
      */
-    #[\ReturnTypeWillChange]
     public function rewind(): void
     {
         $this->xmlReader->close();
@@ -151,10 +149,14 @@ class RowIterator implements IteratorInterface
      *
      * @see http://php.net/manual/en/iterator.valid.php
      */
-    #[\ReturnTypeWillChange]
     public function valid(): bool
     {
-        return !$this->hasReachedEndOfFile;
+        $valid = !$this->hasReachedEndOfFile;
+        if (!$valid) {
+            $this->xmlReader->close();
+        }
+
+        return $valid;
     }
 
     /**
@@ -165,7 +167,6 @@ class RowIterator implements IteratorInterface
      * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If a shared string was not found
      * @throws \OpenSpout\Common\Exception\IOException                   If unable to read the sheet data XML
      */
-    #[\ReturnTypeWillChange]
     public function next(): void
     {
         ++$this->nextRowIndexToBeProcessed;
@@ -180,8 +181,7 @@ class RowIterator implements IteratorInterface
      *
      * @see http://php.net/manual/en/iterator.current.php
      */
-    #[\ReturnTypeWillChange]
-    public function current(): ?Row
+    public function current(): Row
     {
         $rowToBeProcessed = $this->rowBuffer;
 
@@ -193,10 +193,12 @@ class RowIterator implements IteratorInterface
             if ($this->lastRowIndexProcessed !== $this->nextRowIndexToBeProcessed) {
                 // return empty row if mismatch between last processed row
                 // and the row that needs to be returned
-                $rowToBeProcessed = $this->entityFactory->createRow();
+                $rowToBeProcessed = new Row([], null);
             }
         }
 
+        \assert(null !== $rowToBeProcessed);
+
         return $rowToBeProcessed;
     }
 
@@ -205,7 +207,6 @@ class RowIterator implements IteratorInterface
      *
      * @see http://php.net/manual/en/iterator.key.php
      */
-    #[\ReturnTypeWillChange]
     public function key(): int
     {
         // TODO: This should return $this->nextRowIndexToBeProcessed
@@ -216,22 +217,13 @@ class RowIterator implements IteratorInterface
                 $this->numReadRows;
     }
 
-    /**
-     * Cleans up what was created to iterate over the object.
-     */
-    #[\ReturnTypeWillChange]
-    public function end(): void
-    {
-        $this->xmlReader->close();
-    }
-
     /**
      * @param string $sheetDataXMLFilePath Path of the sheet data XML file as in [Content_Types].xml
      *
      * @return string path of the XML file containing the sheet data,
      *                without the leading slash
      */
-    protected function normalizeSheetDataXMLFilePath($sheetDataXMLFilePath)
+    private function normalizeSheetDataXMLFilePath(string $sheetDataXMLFilePath): string
     {
         return ltrim($sheetDataXMLFilePath, '/');
     }
@@ -248,7 +240,7 @@ class RowIterator implements IteratorInterface
      *
      * @return bool whether we need data for the next row to be processed
      */
-    protected function doesNeedDataForNextRowToBeProcessed()
+    private function doesNeedDataForNextRowToBeProcessed(): bool
     {
         $hasReadAtLeastOneRow = (0 !== $this->lastRowIndexProcessed);
 
@@ -263,29 +255,26 @@ class RowIterator implements IteratorInterface
      * @throws \OpenSpout\Reader\Exception\SharedStringNotFoundException If a shared string was not found
      * @throws \OpenSpout\Common\Exception\IOException                   If unable to read the sheet data XML
      */
-    protected function readDataForNextRow()
+    private function readDataForNextRow(): void
     {
-        $this->currentlyProcessedRow = $this->entityFactory->createRow();
+        $this->currentlyProcessedRow = new Row([], null);
 
-        try {
-            $this->xmlProcessor->readUntilStopped();
-        } catch (XMLProcessingException $exception) {
-            throw new IOException("The {$this->sheetDataXMLFilePath} file cannot be read. [{$exception->getMessage()}]");
-        }
+        $this->xmlProcessor->readUntilStopped();
 
         $this->rowBuffer = $this->currentlyProcessedRow;
     }
 
     /**
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XMLReader object, positioned on a "<dimension>" starting node
+     * @param XMLReader $xmlReader XMLReader object, positioned on a "<dimension>" starting node
      *
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processDimensionStartingNode($xmlReader)
+    private function processDimensionStartingNode(XMLReader $xmlReader): int
     {
         // Read dimensions of the sheet
         $dimensionRef = $xmlReader->getAttribute(self::XML_ATTRIBUTE_REF); // returns 'A1:M13' for instance (or 'A1' for empty sheet)
-        if (preg_match('/[A-Z]+\d+:([A-Z]+\d+)/', $dimensionRef, $matches)) {
+        \assert(null !== $dimensionRef);
+        if (1 === preg_match('/[A-Z]+\d+:([A-Z]+\d+)/', $dimensionRef, $matches)) {
             $this->numColumns = CellHelper::getColumnIndexFromCellIndex($matches[1]) + 1;
         }
 
@@ -293,11 +282,11 @@ class RowIterator implements IteratorInterface
     }
 
     /**
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XMLReader object, positioned on a "<row>" starting node
+     * @param XMLReader $xmlReader XMLReader object, positioned on a "<row>" starting node
      *
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processRowStartingNode($xmlReader)
+    private function processRowStartingNode(XMLReader $xmlReader): int
     {
         // Reset index of the last processed column
         $this->lastColumnIndexProcessed = -1;
@@ -308,28 +297,28 @@ class RowIterator implements IteratorInterface
         // Read spans info if present
         $numberOfColumnsForRow = $this->numColumns;
         $spans = $xmlReader->getAttribute(self::XML_ATTRIBUTE_SPANS); // returns '1:5' for instance
-        if ($spans) {
+        if (null !== $spans) {
             [, $numberOfColumnsForRow] = explode(':', $spans);
             $numberOfColumnsForRow = (int) $numberOfColumnsForRow;
         }
 
-        $cells = array_fill(0, $numberOfColumnsForRow, $this->entityFactory->createCell(''));
+        $cells = array_fill(0, $numberOfColumnsForRow, Cell::fromValue(''));
         $this->currentlyProcessedRow->setCells($cells);
 
         return XMLProcessor::PROCESSING_CONTINUE;
     }
 
     /**
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XMLReader object, positioned on a "<cell>" starting node
+     * @param XMLReader $xmlReader XMLReader object, positioned on a "<cell>" starting node
      *
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processCellStartingNode($xmlReader)
+    private function processCellStartingNode(XMLReader $xmlReader): int
     {
         $currentColumnIndex = $this->getColumnIndex($xmlReader);
 
         // NOTE: expand() will automatically decode all XML entities of the child nodes
-        /** @var \DOMElement $node */
+        /** @var DOMElement $node */
         $node = $xmlReader->expand();
         $cell = $this->getCell($node);
 
@@ -342,10 +331,10 @@ class RowIterator implements IteratorInterface
     /**
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processRowEndingNode()
+    private function processRowEndingNode(): int
     {
         // if the fetched row is empty and we don't want to preserve it..,
-        if (!$this->shouldPreserveEmptyRows && $this->rowManager->isEmpty($this->currentlyProcessedRow)) {
+        if (!$this->shouldPreserveEmptyRows && $this->currentlyProcessedRow->isEmpty()) {
             // ... skip it
             return XMLProcessor::PROCESSING_CONTINUE;
         }
@@ -354,7 +343,7 @@ class RowIterator implements IteratorInterface
 
         // If needed, we fill the empty cells
         if (0 === $this->numColumns) {
-            $this->currentlyProcessedRow = $this->rowManager->fillMissingIndexesWithEmptyCells($this->currentlyProcessedRow);
+            $this->rowManager->fillMissingIndexesWithEmptyCells($this->currentlyProcessedRow);
         }
 
         // at this point, we have all the data we need for the row
@@ -365,7 +354,7 @@ class RowIterator implements IteratorInterface
     /**
      * @return int A return code that indicates what action should the processor take next
      */
-    protected function processWorksheetEndingNode()
+    private function processWorksheetEndingNode(): int
     {
         // The closing "</worksheet>" marks the end of the file
         $this->hasReachedEndOfFile = true;
@@ -374,13 +363,13 @@ class RowIterator implements IteratorInterface
     }
 
     /**
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XMLReader object, positioned on a "<row>" node
-     *
-     * @throws \OpenSpout\Common\Exception\InvalidArgumentException When the given cell index is invalid
+     * @param XMLReader $xmlReader XMLReader object, positioned on a "<row>" node
      *
      * @return int Row index
+     *
+     *@throws \OpenSpout\Common\Exception\InvalidArgumentException When the given cell index is invalid
      */
-    protected function getRowIndex($xmlReader)
+    private function getRowIndex(XMLReader $xmlReader): int
     {
         // Get "r" attribute if present (from something like <row r="3"...>
         $currentRowIndex = $xmlReader->getAttribute(self::XML_ATTRIBUTE_ROW_INDEX);
@@ -391,13 +380,13 @@ class RowIterator implements IteratorInterface
     }
 
     /**
-     * @param \OpenSpout\Reader\Wrapper\XMLReader $xmlReader XMLReader object, positioned on a "<c>" node
-     *
-     * @throws \OpenSpout\Common\Exception\InvalidArgumentException When the given cell index is invalid
+     * @param XMLReader $xmlReader XMLReader object, positioned on a "<c>" node
      *
      * @return int Column index
+     *
+     *@throws \OpenSpout\Common\Exception\InvalidArgumentException When the given cell index is invalid
      */
-    protected function getColumnIndex($xmlReader)
+    private function getColumnIndex(XMLReader $xmlReader): int
     {
         // Get "r" attribute if present (from something like <c r="A1"...>
         $currentCellIndex = $xmlReader->getAttribute(self::XML_ATTRIBUTE_CELL_INDEX);
@@ -410,18 +399,15 @@ class RowIterator implements IteratorInterface
     /**
      * Returns the cell with (unescaped) correctly marshalled, cell value associated to the given XML node.
      *
-     * @param \DOMElement $node
-     *
      * @return Cell The cell set with the associated with the cell
      */
-    protected function getCell($node)
+    private function getCell(DOMElement $node): Cell
     {
         try {
             $cellValue = $this->cellValueFormatter->extractAndFormatNodeValue($node);
-            $cell = $this->entityFactory->createCell($cellValue);
+            $cell = Cell::fromValue($cellValue);
         } catch (InvalidValueException $exception) {
-            $cell = $this->entityFactory->createCell($exception->getInvalidValue());
-            $cell->setType(Cell::TYPE_ERROR);
+            $cell = new Cell\ErrorCell($exception->getInvalidValue(), null);
         }
 
         return $cell;
diff --git a/lib/openspout/src/Reader/XLSX/Sheet.php b/lib/openspout/src/Reader/XLSX/Sheet.php
index 64d76374b37..dc671234f75 100644
--- a/lib/openspout/src/Reader/XLSX/Sheet.php
+++ b/lib/openspout/src/Reader/XLSX/Sheet.php
@@ -1,28 +1,34 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX;
 
-use OpenSpout\Reader\SheetInterface;
+use OpenSpout\Reader\Common\ColumnWidth;
+use OpenSpout\Reader\SheetWithVisibilityInterface;
 
 /**
- * Represents a sheet within a XLSX file.
+ * @implements SheetWithVisibilityInterface<RowIterator>
  */
-class Sheet implements SheetInterface
+final class Sheet implements SheetWithVisibilityInterface
 {
-    /** @var \OpenSpout\Reader\XLSX\RowIterator To iterate over sheet's rows */
-    protected $rowIterator;
+    /** @var RowIterator To iterate over sheet's rows */
+    private RowIterator $rowIterator;
+
+    /** @var SheetHeaderReader To read the header of the sheet, containing for instance the col widths */
+    private SheetHeaderReader $headerReader;
 
     /** @var int Index of the sheet, based on order in the workbook (zero-based) */
-    protected $index;
+    private int $index;
 
     /** @var string Name of the sheet */
-    protected $name;
+    private string $name;
 
     /** @var bool Whether the sheet was the active one */
-    protected $isActive;
+    private bool $isActive;
 
     /** @var bool Whether the sheet is visible */
-    protected $isVisible;
+    private bool $isVisible;
 
     /**
      * @param RowIterator $rowIterator    The corresponding row iterator
@@ -31,27 +37,33 @@ class Sheet implements SheetInterface
      * @param bool        $isSheetActive  Whether the sheet was defined as active
      * @param bool        $isSheetVisible Whether the sheet is visible
      */
-    public function __construct($rowIterator, $sheetIndex, $sheetName, $isSheetActive, $isSheetVisible)
+    public function __construct(RowIterator $rowIterator, SheetHeaderReader $headerReader, int $sheetIndex, string $sheetName, bool $isSheetActive, bool $isSheetVisible)
     {
         $this->rowIterator = $rowIterator;
+        $this->headerReader = $headerReader;
         $this->index = $sheetIndex;
         $this->name = $sheetName;
         $this->isActive = $isSheetActive;
         $this->isVisible = $isSheetVisible;
     }
 
-    /**
-     * @return \OpenSpout\Reader\XLSX\RowIterator
-     */
-    public function getRowIterator()
+    public function getRowIterator(): RowIterator
     {
         return $this->rowIterator;
     }
 
+    /**
+     * @return ColumnWidth[] a list of column-widths
+     */
+    public function getColumnWidths(): array
+    {
+        return $this->headerReader->getColumnWidths();
+    }
+
     /**
      * @return int Index of the sheet, based on order in the workbook (zero-based)
      */
-    public function getIndex()
+    public function getIndex(): int
     {
         return $this->index;
     }
@@ -59,7 +71,7 @@ class Sheet implements SheetInterface
     /**
      * @return string Name of the sheet
      */
-    public function getName()
+    public function getName(): string
     {
         return $this->name;
     }
@@ -67,7 +79,7 @@ class Sheet implements SheetInterface
     /**
      * @return bool Whether the sheet was defined as active
      */
-    public function isActive()
+    public function isActive(): bool
     {
         return $this->isActive;
     }
@@ -75,7 +87,7 @@ class Sheet implements SheetInterface
     /**
      * @return bool Whether the sheet is visible
      */
-    public function isVisible()
+    public function isVisible(): bool
     {
         return $this->isVisible;
     }
diff --git a/lib/openspout/src/Reader/XLSX/SheetHeaderReader.php b/lib/openspout/src/Reader/XLSX/SheetHeaderReader.php
new file mode 100644
index 00000000000..ea4be2bb749
--- /dev/null
+++ b/lib/openspout/src/Reader/XLSX/SheetHeaderReader.php
@@ -0,0 +1,119 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Reader\XLSX;
+
+use OpenSpout\Common\Exception\IOException;
+use OpenSpout\Reader\Common\ColumnWidth;
+use OpenSpout\Reader\Common\XMLProcessor;
+use OpenSpout\Reader\Wrapper\XMLReader;
+
+final class SheetHeaderReader
+{
+    public const XML_NODE_COL = 'col';
+    public const XML_NODE_SHEETDATA = 'sheetData';
+    public const XML_ATTRIBUTE_MIN = 'min';
+    public const XML_ATTRIBUTE_MAX = 'max';
+    public const XML_ATTRIBUTE_WIDTH = 'width';
+
+    /** @var string Path of the XLSX file being read */
+    private string $filePath;
+
+    /** @var string Path of the sheet data XML file as in [Content_Types].xml */
+    private string $sheetDataXMLFilePath;
+
+    /** @var XMLReader The XMLReader object that will help read sheet's XML data */
+    private XMLReader $xmlReader;
+
+    /** @var XMLProcessor Helper Object to process XML nodes */
+    private XMLProcessor $xmlProcessor;
+
+    /** @var ColumnWidth[] The widths of the columns in the sheet, if specified */
+    private array $columnWidths = [];
+
+    /**
+     * @param string       $filePath             Path of the XLSX file being read
+     * @param string       $sheetDataXMLFilePath Path of the sheet data XML file as in [Content_Types].xml
+     * @param XMLReader    $xmlReader            XML Reader
+     * @param XMLProcessor $xmlProcessor         Helper to process XML files
+     */
+    public function __construct(
+        string $filePath,
+        string $sheetDataXMLFilePath,
+        XMLReader $xmlReader,
+        XMLProcessor $xmlProcessor
+    ) {
+        $this->filePath = $filePath;
+        $this->sheetDataXMLFilePath = $this->normalizeSheetDataXMLFilePath($sheetDataXMLFilePath);
+        $this->xmlReader = $xmlReader;
+
+        // Register all callbacks to process different nodes when reading the XML file
+        $this->xmlProcessor = $xmlProcessor;
+        $this->xmlProcessor->registerCallback(self::XML_NODE_COL, XMLProcessor::NODE_TYPE_START, [$this, 'processColStartingNode']);
+        $this->xmlProcessor->registerCallback(self::XML_NODE_SHEETDATA, XMLProcessor::NODE_TYPE_START, [$this, 'processSheetDataStartingNode']);
+
+        // The reader should be unused, but we close to be sure
+        $this->xmlReader->close();
+
+        if (false === $this->xmlReader->openFileInZip($this->filePath, $this->sheetDataXMLFilePath)) {
+            throw new IOException("Could not open \"{$this->sheetDataXMLFilePath}\".");
+        }
+
+        // Now read the entire header of the sheet, until we reach the <sheetData> element
+        $this->xmlProcessor->readUntilStopped();
+
+        // We don't need the reader anymore, so we close it
+        $this->xmlReader->close();
+    }
+
+    /**
+     * @internal
+     *
+     * @return ColumnWidth[]
+     */
+    public function getColumnWidths(): array
+    {
+        return $this->columnWidths;
+    }
+
+    /**
+     * @param XMLReader $xmlReader XMLReader object, positioned on a "<col>" starting node
+     *
+     * @return int A return code that indicates what action should the processor take next
+     */
+    private function processColStartingNode(XMLReader $xmlReader): int
+    {
+        $min = (int) $xmlReader->getAttribute(self::XML_ATTRIBUTE_MIN);
+        $max = (int) $xmlReader->getAttribute(self::XML_ATTRIBUTE_MAX);
+        $width = (float) $xmlReader->getAttribute(self::XML_ATTRIBUTE_WIDTH);
+
+        \assert($min > 0);
+        \assert($max > 0);
+
+        $columnwidth = new ColumnWidth($min, $max, $width);
+        $this->columnWidths[] = $columnwidth;
+
+        return XMLProcessor::PROCESSING_CONTINUE;
+    }
+
+    /**
+     * @return int A return code that indicates what action should the processor take next
+     */
+    private function processSheetDataStartingNode(): int
+    {
+        // The opening "<sheetData>" marks the end of the file
+        return XMLProcessor::PROCESSING_STOP;
+    }
+
+    /**
+     * @param string $sheetDataXMLFilePath Path of the sheet data XML file as in [Content_Types].xml
+     *
+     * @return string path of the XML file containing the sheet data,
+     *                without the leading slash
+     */
+    private function normalizeSheetDataXMLFilePath(string $sheetDataXMLFilePath): string
+    {
+        return ltrim($sheetDataXMLFilePath, '/');
+    }
+}
diff --git a/lib/openspout/src/Reader/XLSX/SheetIterator.php b/lib/openspout/src/Reader/XLSX/SheetIterator.php
index f58fc672cc0..33b26f912be 100644
--- a/lib/openspout/src/Reader/XLSX/SheetIterator.php
+++ b/lib/openspout/src/Reader/XLSX/SheetIterator.php
@@ -1,28 +1,30 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Reader\XLSX;
 
 use OpenSpout\Reader\Exception\NoSheetsFoundException;
-use OpenSpout\Reader\IteratorInterface;
+use OpenSpout\Reader\SheetIteratorInterface;
 use OpenSpout\Reader\XLSX\Manager\SheetManager;
 
 /**
- * Iterate over XLSX sheet.
+ * @implements SheetIteratorInterface<Sheet>
  */
-class SheetIterator implements IteratorInterface
+final class SheetIterator implements SheetIteratorInterface
 {
-    /** @var \OpenSpout\Reader\XLSX\Sheet[] The list of sheet present in the file */
-    protected $sheets;
+    /** @var Sheet[] The list of sheet present in the file */
+    private array $sheets;
 
     /** @var int The index of the sheet being read (zero-based) */
-    protected $currentSheetIndex;
+    private int $currentSheetIndex = 0;
 
     /**
      * @param SheetManager $sheetManager Manages sheets
      *
-     * @throws \OpenSpout\Reader\Exception\NoSheetsFoundException If there are no sheets in the file
+     * @throws NoSheetsFoundException If there are no sheets in the file
      */
-    public function __construct($sheetManager)
+    public function __construct(SheetManager $sheetManager)
     {
         // Fetch all available sheets
         $this->sheets = $sheetManager->getSheets();
@@ -37,8 +39,7 @@ class SheetIterator implements IteratorInterface
      *
      * @see http://php.net/manual/en/iterator.rewind.php
      */
-    #[\ReturnTypeWillChange]
-    public function rewind()
+    public function rewind(): void
     {
         $this->currentSheetIndex = 0;
     }
@@ -47,11 +48,8 @@ class SheetIterator implements IteratorInterface
      * Checks if current position is valid.
      *
      * @see http://php.net/manual/en/iterator.valid.php
-     *
-     * @return bool
      */
-    #[\ReturnTypeWillChange]
-    public function valid()
+    public function valid(): bool
     {
         return $this->currentSheetIndex < \count($this->sheets);
     }
@@ -61,27 +59,17 @@ class SheetIterator implements IteratorInterface
      *
      * @see http://php.net/manual/en/iterator.next.php
      */
-    #[\ReturnTypeWillChange]
-    public function next()
+    public function next(): void
     {
-        // Using isset here because it is way faster than array_key_exists...
-        if (isset($this->sheets[$this->currentSheetIndex])) {
-            $currentSheet = $this->sheets[$this->currentSheetIndex];
-            $currentSheet->getRowIterator()->end();
-
-            ++$this->currentSheetIndex;
-        }
+        ++$this->currentSheetIndex;
     }
 
     /**
      * Return the current element.
      *
      * @see http://php.net/manual/en/iterator.current.php
-     *
-     * @return \OpenSpout\Reader\XLSX\Sheet
      */
-    #[\ReturnTypeWillChange]
-    public function current()
+    public function current(): Sheet
     {
         return $this->sheets[$this->currentSheetIndex];
     }
@@ -90,24 +78,9 @@ class SheetIterator implements IteratorInterface
      * Return the key of the current element.
      *
      * @see http://php.net/manual/en/iterator.key.php
-     *
-     * @return int
      */
-    #[\ReturnTypeWillChange]
-    public function key()
+    public function key(): int
     {
         return $this->currentSheetIndex + 1;
     }
-
-    /**
-     * Cleans up what was created to iterate over the object.
-     */
-    #[\ReturnTypeWillChange]
-    public function end()
-    {
-        // make sure we are not leaking memory in case the iteration stopped before the end
-        foreach ($this->sheets as $sheet) {
-            $sheet->getRowIterator()->end();
-        }
-    }
 }
diff --git a/lib/openspout/src/Writer/AbstractWriter.php b/lib/openspout/src/Writer/AbstractWriter.php
new file mode 100644
index 00000000000..9f0633a5ea6
--- /dev/null
+++ b/lib/openspout/src/Writer/AbstractWriter.php
@@ -0,0 +1,175 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Writer;
+
+use OpenSpout\Common\Entity\Row;
+use OpenSpout\Common\Exception\IOException;
+use OpenSpout\Writer\Exception\WriterNotOpenedException;
+
+abstract class AbstractWriter implements WriterInterface
+{
+    /** @var resource Pointer to the file/stream we will write to */
+    protected $filePointer;
+
+    /** @var string Content-Type value for the header - to be defined by child class */
+    protected static string $headerContentType;
+
+    /** @var string Path to the output file */
+    private string $outputFilePath;
+
+    /** @var bool Indicates whether the writer has been opened or not */
+    private bool $isWriterOpened = false;
+
+    /** @var 0|positive-int */
+    private int $writtenRowCount = 0;
+
+    /**
+     * {@inheritdoc}
+     */
+    final public function openToFile($outputFilePath): void
+    {
+        $this->outputFilePath = $outputFilePath;
+
+        $errorMessage = null;
+        set_error_handler(static function ($nr, $message) use (&$errorMessage): bool {
+            $errorMessage = $message;
+
+            return true;
+        });
+
+        $resource = fopen($this->outputFilePath, 'w');
+        restore_error_handler();
+        if (null !== $errorMessage) {
+            throw new IOException("Unable to open file {$this->outputFilePath}: {$errorMessage}");
+        }
+        \assert(false !== $resource);
+        $this->filePointer = $resource;
+
+        $this->openWriter();
+        $this->isWriterOpened = true;
+    }
+
+    /**
+     * @codeCoverageIgnore
+     * {@inheritdoc}
+     */
+    final public function openToBrowser($outputFileName): void
+    {
+        $this->outputFilePath = basename($outputFileName);
+
+        $resource = fopen('php://output', 'w');
+        \assert(false !== $resource);
+        $this->filePointer = $resource;
+
+        // Clear any previous output (otherwise the generated file will be corrupted)
+        // @see https://github.com/box/spout/issues/241
+        if (ob_get_length() > 0) {
+            ob_end_clean();
+        }
+
+        /*
+         * Set headers
+         *
+         * For newer browsers such as Firefox, Chrome, Opera, Safari, etc., they all support and use `filename*`
+         * specified by the new standard, even if they do not automatically decode filename; it does not matter;
+         * and for older versions of Internet Explorer, they are not recognized `filename*`, will automatically
+         * ignore it and use the old `filename` (the only minor flaw is that there must be an English suffix name).
+         * In this way, the multi-browser multi-language compatibility problem is perfectly solved, which does not
+         * require UA judgment and is more in line with the standard.
+         *
+         * @see https://github.com/box/spout/issues/745
+         * @see https://tools.ietf.org/html/rfc6266
+         * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Disposition
+         */
+        header('Content-Type: '.static::$headerContentType);
+        header(
+            'Content-Disposition: attachment; '.
+            'filename="'.rawurlencode($this->outputFilePath).'"; '.
+            'filename*=UTF-8\'\''.rawurlencode($this->outputFilePath)
+        );
+
+        /*
+         * When forcing the download of a file over SSL,IE8 and lower browsers fail
+         * if the Cache-Control and Pragma headers are not set.
+         *
+         * @see http://support.microsoft.com/KB/323308
+         * @see https://github.com/liuggio/ExcelBundle/issues/45
+         */
+        header('Cache-Control: max-age=0');
+        header('Pragma: public');
+
+        $this->openWriter();
+        $this->isWriterOpened = true;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    final public function addRow(Row $row): void
+    {
+        if (!$this->isWriterOpened) {
+            throw new WriterNotOpenedException('The writer needs to be opened before adding row.');
+        }
+
+        $this->addRowToWriter($row);
+        ++$this->writtenRowCount;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    final public function addRows(array $rows): void
+    {
+        foreach ($rows as $row) {
+            $this->addRow($row);
+        }
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    final public function getWrittenRowCount(): int
+    {
+        return $this->writtenRowCount;
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    final public function close(): void
+    {
+        if (!$this->isWriterOpened) {
+            return;
+        }
+
+        $this->closeWriter();
+
+        fclose($this->filePointer);
+
+        $this->isWriterOpened = false;
+    }
+
+    /**
+     * Opens the streamer and makes it ready to accept data.
+     *
+     * @throws IOException If the writer cannot be opened
+     */
+    abstract protected function openWriter(): void;
+
+    /**
+     * Adds a row to the currently opened writer.
+     *
+     * @param Row $row The row containing cells and styles
+     *
+     * @throws WriterNotOpenedException If the workbook is not created yet
+     * @throws IOException              If unable to write data
+     */
+    abstract protected function addRowToWriter(Row $row): void;
+
+    /**
+     * Closes the streamer, preventing any additional writing.
+     */
+    abstract protected function closeWriter(): void;
+}
diff --git a/lib/openspout/src/Writer/AbstractWriterMultiSheets.php b/lib/openspout/src/Writer/AbstractWriterMultiSheets.php
new file mode 100644
index 00000000000..be61aa07011
--- /dev/null
+++ b/lib/openspout/src/Writer/AbstractWriterMultiSheets.php
@@ -0,0 +1,129 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Writer;
+
+use OpenSpout\Common\Entity\Row;
+use OpenSpout\Common\Exception\IOException;
+use OpenSpout\Writer\Common\Entity\Sheet;
+use OpenSpout\Writer\Common\Manager\WorkbookManagerInterface;
+use OpenSpout\Writer\Exception\SheetNotFoundException;
+use OpenSpout\Writer\Exception\WriterNotOpenedException;
+
+abstract class AbstractWriterMultiSheets extends AbstractWriter
+{
+    private WorkbookManagerInterface $workbookManager;
+
+    /**
+     * Returns all the workbook's sheets.
+     *
+     * @return Sheet[] All the workbook's sheets
+     *
+     * @throws WriterNotOpenedException If the writer has not been opened yet
+     */
+    final public function getSheets(): array
+    {
+        $this->throwIfWorkbookIsNotAvailable();
+
+        $externalSheets = [];
+        $worksheets = $this->workbookManager->getWorksheets();
+
+        foreach ($worksheets as $worksheet) {
+            $externalSheets[] = $worksheet->getExternalSheet();
+        }
+
+        return $externalSheets;
+    }
+
+    /**
+     * Creates a new sheet and make it the current sheet. The data will now be written to this sheet.
+     *
+     * @return Sheet The created sheet
+     *
+     * @throws IOException
+     * @throws WriterNotOpenedException If the writer has not been opened yet
+     */
+    final public function addNewSheetAndMakeItCurrent(): Sheet
+    {
+        $this->throwIfWorkbookIsNotAvailable();
+        $worksheet = $this->workbookManager->addNewSheetAndMakeItCurrent();
+
+        return $worksheet->getExternalSheet();
+    }
+
+    /**
+     * Returns the current sheet.
+     *
+     * @return Sheet The current sheet
+     *
+     * @throws WriterNotOpenedException If the writer has not been opened yet
+     */
+    final public function getCurrentSheet(): Sheet
+    {
+        $this->throwIfWorkbookIsNotAvailable();
+
+        return $this->workbookManager->getCurrentWorksheet()->getExternalSheet();
+    }
+
+    /**
+     * Sets the given sheet as the current one. New data will be written to this sheet.
+     * The writing will resume where it stopped (i.e. data won't be truncated).
+     *
+     * @param Sheet $sheet The sheet to set as current
+     *
+     * @throws SheetNotFoundException   If the given sheet does not exist in the workbook
+     * @throws WriterNotOpenedException If the writer has not been opened yet
+     */
+    final public function setCurrentSheet(Sheet $sheet): void
+    {
+        $this->throwIfWorkbookIsNotAvailable();
+        $this->workbookManager->setCurrentSheet($sheet);
+    }
+
+    abstract protected function createWorkbookManager(): WorkbookManagerInterface;
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function openWriter(): void
+    {
+        if (!isset($this->workbookManager)) {
+            $this->workbookManager = $this->createWorkbookManager();
+            $this->workbookManager->addNewSheetAndMakeItCurrent();
+        }
+    }
+
+    /**
+     * {@inheritdoc}
+     *
+     * @throws Exception\WriterException
+     */
+    protected function addRowToWriter(Row $row): void
+    {
+        $this->throwIfWorkbookIsNotAvailable();
+        $this->workbookManager->addRowToCurrentWorksheet($row);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    protected function closeWriter(): void
+    {
+        if (isset($this->workbookManager)) {
+            $this->workbookManager->close($this->filePointer);
+        }
+    }
+
+    /**
+     * Checks if the workbook has been created. Throws an exception if not created yet.
+     *
+     * @throws WriterNotOpenedException If the workbook is not created yet
+     */
+    private function throwIfWorkbookIsNotAvailable(): void
+    {
+        if (!isset($this->workbookManager)) {
+            throw new WriterNotOpenedException('The writer must be opened before performing this action.');
+        }
+    }
+}
diff --git a/lib/openspout/src/Writer/AutoFilter.php b/lib/openspout/src/Writer/AutoFilter.php
new file mode 100644
index 00000000000..b9796446457
--- /dev/null
+++ b/lib/openspout/src/Writer/AutoFilter.php
@@ -0,0 +1,25 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Writer;
+
+/**
+ * @readonly
+ */
+final class AutoFilter
+{
+    /**
+     * @param 0|positive-int $fromColumnIndex
+     * @param positive-int   $fromRow
+     * @param 0|positive-int $toColumnIndex
+     * @param positive-int   $toRow
+     */
+    public function __construct(
+        public int $fromColumnIndex,
+        public int $fromRow,
+        public int $toColumnIndex,
+        public int $toRow
+    ) {
+    }
+}
diff --git a/lib/openspout/src/Writer/CSV/Manager/OptionsManager.php b/lib/openspout/src/Writer/CSV/Manager/OptionsManager.php
deleted file mode 100644
index c6e25a6a073..00000000000
--- a/lib/openspout/src/Writer/CSV/Manager/OptionsManager.php
+++ /dev/null
@@ -1,34 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\CSV\Manager;
-
-use OpenSpout\Common\Manager\OptionsManagerAbstract;
-use OpenSpout\Writer\Common\Entity\Options;
-
-/**
- * CSV Writer options manager.
- */
-class OptionsManager extends OptionsManagerAbstract
-{
-    /**
-     * {@inheritdoc}
-     */
-    protected function getSupportedOptions()
-    {
-        return [
-            Options::FIELD_DELIMITER,
-            Options::FIELD_ENCLOSURE,
-            Options::SHOULD_ADD_BOM,
-        ];
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function setDefaultOptions()
-    {
-        $this->setOption(Options::FIELD_DELIMITER, ',');
-        $this->setOption(Options::FIELD_ENCLOSURE, '"');
-        $this->setOption(Options::SHOULD_ADD_BOM, true);
-    }
-}
diff --git a/lib/openspout/src/Writer/CSV/Options.php b/lib/openspout/src/Writer/CSV/Options.php
new file mode 100644
index 00000000000..6a0eb510e95
--- /dev/null
+++ b/lib/openspout/src/Writer/CSV/Options.php
@@ -0,0 +1,15 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Writer\CSV;
+
+final class Options
+{
+    public string $FIELD_DELIMITER = ',';
+    public string $FIELD_ENCLOSURE = '"';
+    public bool $SHOULD_ADD_BOM = true;
+
+    /** @var positive-int */
+    public int $FLUSH_THRESHOLD = 500;
+}
diff --git a/lib/openspout/src/Writer/CSV/Writer.php b/lib/openspout/src/Writer/CSV/Writer.php
index 2815d0e19c0..f3d94e487b0 100644
--- a/lib/openspout/src/Writer/CSV/Writer.php
+++ b/lib/openspout/src/Writer/CSV/Writer.php
@@ -1,77 +1,42 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\CSV;
 
+use OpenSpout\Common\Entity\Cell;
 use OpenSpout\Common\Entity\Row;
 use OpenSpout\Common\Exception\IOException;
 use OpenSpout\Common\Helper\EncodingHelper;
-use OpenSpout\Writer\Common\Entity\Options;
-use OpenSpout\Writer\WriterAbstract;
+use OpenSpout\Writer\AbstractWriter;
 
-/**
- * This class provides support to write data to CSV files.
- */
-class Writer extends WriterAbstract
+final class Writer extends AbstractWriter
 {
-    /** Number of rows to write before flushing */
-    public const FLUSH_THRESHOLD = 500;
-
     /** @var string Content-Type value for the header */
-    protected static $headerContentType = 'text/csv; charset=UTF-8';
+    protected static string $headerContentType = 'text/csv; charset=UTF-8';
 
-    /** @var int */
-    protected $lastWrittenRowIndex = 0;
+    private Options $options;
 
-    /**
-     * Sets the field delimiter for the CSV.
-     *
-     * @param string $fieldDelimiter Character that delimits fields
-     *
-     * @return Writer
-     */
-    public function setFieldDelimiter($fieldDelimiter)
+    private int $lastWrittenRowIndex = 0;
+
+    public function __construct(?Options $options = null)
     {
-        $this->optionsManager->setOption(Options::FIELD_DELIMITER, $fieldDelimiter);
-
-        return $this;
+        $this->options = $options ?? new Options();
     }
 
-    /**
-     * Sets the field enclosure for the CSV.
-     *
-     * @param string $fieldEnclosure Character that enclose fields
-     *
-     * @return Writer
-     */
-    public function setFieldEnclosure($fieldEnclosure)
+    public function getOptions(): Options
     {
-        $this->optionsManager->setOption(Options::FIELD_ENCLOSURE, $fieldEnclosure);
-
-        return $this;
-    }
-
-    /**
-     * Set if a BOM has to be added to the file.
-     *
-     * @param bool $shouldAddBOM
-     *
-     * @return Writer
-     */
-    public function setShouldAddBOM($shouldAddBOM)
-    {
-        $this->optionsManager->setOption(Options::SHOULD_ADD_BOM, (bool) $shouldAddBOM);
-
-        return $this;
+        return $this->options;
     }
 
     /**
      * Opens the CSV streamer and makes it ready to accept data.
      */
-    protected function openWriter()
+    protected function openWriter(): void
     {
-        if ($this->optionsManager->getOption(Options::SHOULD_ADD_BOM)) {
+        if ($this->options->SHOULD_ADD_BOM) {
             // Adds UTF-8 BOM for Unicode compatibility
-            $this->globalFunctionsHelper->fputs($this->filePointer, EncodingHelper::BOM_UTF8);
+            fwrite($this->filePointer, EncodingHelper::BOM_UTF8);
         }
     }
 
@@ -82,19 +47,30 @@ class Writer extends WriterAbstract
      *
      * @throws IOException If unable to write data
      */
-    protected function addRowToWriter(Row $row)
+    protected function addRowToWriter(Row $row): void
     {
-        $fieldDelimiter = $this->optionsManager->getOption(Options::FIELD_DELIMITER);
-        $fieldEnclosure = $this->optionsManager->getOption(Options::FIELD_ENCLOSURE);
+        $cells = array_map(static function (Cell\BooleanCell|Cell\EmptyCell|Cell\NumericCell|Cell\StringCell|Cell\FormulaCell $value): string {
+            if ($value instanceof Cell\BooleanCell) {
+                return (string) (int) $value->getValue();
+            }
 
-        $wasWriteSuccessful = $this->globalFunctionsHelper->fputcsv($this->filePointer, $row->getCells(), $fieldDelimiter, $fieldEnclosure);
+            return (string) $value->getValue();
+        }, $row->getCells());
+
+        $wasWriteSuccessful = fputcsv(
+            $this->filePointer,
+            $cells,
+            $this->options->FIELD_DELIMITER,
+            $this->options->FIELD_ENCLOSURE,
+            ''
+        );
         if (false === $wasWriteSuccessful) {
-            throw new IOException('Unable to write data');
+            throw new IOException('Unable to write data'); // @codeCoverageIgnore
         }
 
         ++$this->lastWrittenRowIndex;
-        if (0 === $this->lastWrittenRowIndex % self::FLUSH_THRESHOLD) {
-            $this->globalFunctionsHelper->fflush($this->filePointer);
+        if (0 === $this->lastWrittenRowIndex % $this->options->FLUSH_THRESHOLD) {
+            fflush($this->filePointer);
         }
     }
 
@@ -102,7 +78,7 @@ class Writer extends WriterAbstract
      * Closes the CSV streamer, preventing any additional writing.
      * If set, sets the headers and redirects output to the browser.
      */
-    protected function closeWriter()
+    protected function closeWriter(): void
     {
         $this->lastWrittenRowIndex = 0;
     }
diff --git a/lib/openspout/src/Writer/Common/AbstractOptions.php b/lib/openspout/src/Writer/Common/AbstractOptions.php
new file mode 100644
index 00000000000..0b6651d84a9
--- /dev/null
+++ b/lib/openspout/src/Writer/Common/AbstractOptions.php
@@ -0,0 +1,67 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Writer\Common;
+
+use OpenSpout\Common\Entity\Style\Style;
+use OpenSpout\Common\TempFolderOptionTrait;
+
+abstract class AbstractOptions
+{
+    use TempFolderOptionTrait;
+
+    public Style $DEFAULT_ROW_STYLE;
+    public bool $SHOULD_CREATE_NEW_SHEETS_AUTOMATICALLY = true;
+    public ?float $DEFAULT_COLUMN_WIDTH = null;
+    public ?float $DEFAULT_ROW_HEIGHT = null;
+
+    /** @var ColumnWidth[] Array of min-max-width arrays */
+    private array $COLUMN_WIDTHS = [];
+
+    public function __construct()
+    {
+        $this->DEFAULT_ROW_STYLE = new Style();
+    }
+
+    /**
+     * @param positive-int ...$columns One or more columns with this width
+     */
+    final public function setColumnWidth(float $width, int ...$columns): void
+    {
+        // Gather sequences
+        $sequence = [];
+        foreach ($columns as $column) {
+            $sequenceLength = \count($sequence);
+            if ($sequenceLength > 0) {
+                $previousValue = $sequence[$sequenceLength - 1];
+                if ($column !== $previousValue + 1) {
+                    $this->setColumnWidthForRange($width, $sequence[0], $previousValue);
+                    $sequence = [];
+                }
+            }
+            $sequence[] = $column;
+        }
+        $this->setColumnWidthForRange($width, $sequence[0], $sequence[\count($sequence) - 1]);
+    }
+
+    /**
+     * @param float        $width The width to set
+     * @param positive-int $start First column index of the range
+     * @param positive-int $end   Last column index of the range
+     */
+    final public function setColumnWidthForRange(float $width, int $start, int $end): void
+    {
+        $this->COLUMN_WIDTHS[] = new ColumnWidth($start, $end, $width);
+    }
+
+    /**
+     * @internal
+     *
+     * @return ColumnWidth[]
+     */
+    final public function getColumnWidths(): array
+    {
+        return $this->COLUMN_WIDTHS;
+    }
+}
diff --git a/lib/openspout/src/Writer/Common/ColumnWidth.php b/lib/openspout/src/Writer/Common/ColumnWidth.php
new file mode 100644
index 00000000000..ba7b8020578
--- /dev/null
+++ b/lib/openspout/src/Writer/Common/ColumnWidth.php
@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Writer\Common;
+
+/**
+ * @internal
+ */
+final class ColumnWidth
+{
+    /**
+     * @param positive-int $start
+     * @param positive-int $end
+     */
+    public function __construct(
+        public int $start,
+        public int $end,
+        public float $width,
+    ) {
+    }
+}
diff --git a/lib/openspout/src/Writer/Common/Creator/InternalEntityFactory.php b/lib/openspout/src/Writer/Common/Creator/InternalEntityFactory.php
deleted file mode 100644
index 63e96d3147f..00000000000
--- a/lib/openspout/src/Writer/Common/Creator/InternalEntityFactory.php
+++ /dev/null
@@ -1,52 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\Common\Creator;
-
-use OpenSpout\Writer\Common\Entity\Sheet;
-use OpenSpout\Writer\Common\Entity\Workbook;
-use OpenSpout\Writer\Common\Entity\Worksheet;
-use OpenSpout\Writer\Common\Manager\SheetManager;
-
-/**
- * Factory to create internal entities.
- */
-class InternalEntityFactory
-{
-    /**
-     * @return Workbook
-     */
-    public function createWorkbook()
-    {
-        return new Workbook();
-    }
-
-    /**
-     * @param string $worksheetFilePath
-     *
-     * @return Worksheet
-     */
-    public function createWorksheet($worksheetFilePath, Sheet $externalSheet)
-    {
-        return new Worksheet($worksheetFilePath, $externalSheet);
-    }
-
-    /**
-     * @param int          $sheetIndex           Index of the sheet, based on order in the workbook (zero-based)
-     * @param string       $associatedWorkbookId ID of the sheet's associated workbook
-     * @param SheetManager $sheetManager         To manage sheets
-     *
-     * @return Sheet
-     */
-    public function createSheet($sheetIndex, $associatedWorkbookId, $sheetManager)
-    {
-        return new Sheet($sheetIndex, $associatedWorkbookId, $sheetManager);
-    }
-
-    /**
-     * @return \ZipArchive
-     */
-    public function createZipArchive()
-    {
-        return new \ZipArchive();
-    }
-}
diff --git a/lib/openspout/src/Writer/Common/Creator/ManagerFactoryInterface.php b/lib/openspout/src/Writer/Common/Creator/ManagerFactoryInterface.php
deleted file mode 100644
index 1e09e62e354..00000000000
--- a/lib/openspout/src/Writer/Common/Creator/ManagerFactoryInterface.php
+++ /dev/null
@@ -1,23 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\Common\Creator;
-
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Writer\Common\Manager\SheetManager;
-use OpenSpout\Writer\Common\Manager\WorkbookManagerInterface;
-
-/**
- * Interface ManagerFactoryInterface.
- */
-interface ManagerFactoryInterface
-{
-    /**
-     * @return WorkbookManagerInterface
-     */
-    public function createWorkbookManager(OptionsManagerInterface $optionsManager);
-
-    /**
-     * @return SheetManager
-     */
-    public function createSheetManager();
-}
diff --git a/lib/openspout/src/Writer/Common/Creator/Style/BorderBuilder.php b/lib/openspout/src/Writer/Common/Creator/Style/BorderBuilder.php
deleted file mode 100644
index 1468f0de9ab..00000000000
--- a/lib/openspout/src/Writer/Common/Creator/Style/BorderBuilder.php
+++ /dev/null
@@ -1,84 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\Common\Creator\Style;
-
-use OpenSpout\Common\Entity\Style\Border;
-use OpenSpout\Common\Entity\Style\BorderPart;
-use OpenSpout\Common\Entity\Style\Color;
-
-class BorderBuilder
-{
-    /**
-     * @var Border
-     */
-    protected $border;
-
-    public function __construct()
-    {
-        $this->border = new Border();
-    }
-
-    /**
-     * @param string $color Border A RGB color code
-     * @param string $width Border width @see BorderPart::allowedWidths
-     * @param string $style Border style @see BorderPart::allowedStyles
-     *
-     * @return BorderBuilder
-     */
-    public function setBorderTop($color = Color::BLACK, $width = Border::WIDTH_MEDIUM, $style = Border::STYLE_SOLID)
-    {
-        $this->border->addPart(new BorderPart(Border::TOP, $color, $width, $style));
-
-        return $this;
-    }
-
-    /**
-     * @param string $color Border A RGB color code
-     * @param string $width Border width @see BorderPart::allowedWidths
-     * @param string $style Border style @see BorderPart::allowedStyles
-     *
-     * @return BorderBuilder
-     */
-    public function setBorderRight($color = Color::BLACK, $width = Border::WIDTH_MEDIUM, $style = Border::STYLE_SOLID)
-    {
-        $this->border->addPart(new BorderPart(Border::RIGHT, $color, $width, $style));
-
-        return $this;
-    }
-
-    /**
-     * @param string $color Border A RGB color code
-     * @param string $width Border width @see BorderPart::allowedWidths
-     * @param string $style Border style @see BorderPart::allowedStyles
-     *
-     * @return BorderBuilder
-     */
-    public function setBorderBottom($color = Color::BLACK, $width = Border::WIDTH_MEDIUM, $style = Border::STYLE_SOLID)
-    {
-        $this->border->addPart(new BorderPart(Border::BOTTOM, $color, $width, $style));
-
-        return $this;
-    }
-
-    /**
-     * @param string $color Border A RGB color code
-     * @param string $width Border width @see BorderPart::allowedWidths
-     * @param string $style Border style @see BorderPart::allowedStyles
-     *
-     * @return BorderBuilder
-     */
-    public function setBorderLeft($color = Color::BLACK, $width = Border::WIDTH_MEDIUM, $style = Border::STYLE_SOLID)
-    {
-        $this->border->addPart(new BorderPart(Border::LEFT, $color, $width, $style));
-
-        return $this;
-    }
-
-    /**
-     * @return Border
-     */
-    public function build()
-    {
-        return $this->border;
-    }
-}
diff --git a/lib/openspout/src/Writer/Common/Creator/Style/StyleBuilder.php b/lib/openspout/src/Writer/Common/Creator/Style/StyleBuilder.php
deleted file mode 100644
index 2ef0d151667..00000000000
--- a/lib/openspout/src/Writer/Common/Creator/Style/StyleBuilder.php
+++ /dev/null
@@ -1,214 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\Common\Creator\Style;
-
-use OpenSpout\Common\Entity\Style\Border;
-use OpenSpout\Common\Entity\Style\CellAlignment;
-use OpenSpout\Common\Entity\Style\Style;
-use OpenSpout\Common\Exception\InvalidArgumentException;
-
-/**
- * Builder to create new styles.
- */
-class StyleBuilder
-{
-    /** @var Style Style to be created */
-    protected $style;
-
-    public function __construct()
-    {
-        $this->style = new Style();
-    }
-
-    /**
-     * Makes the font bold.
-     *
-     * @return StyleBuilder
-     */
-    public function setFontBold()
-    {
-        $this->style->setFontBold();
-
-        return $this;
-    }
-
-    /**
-     * Makes the font italic.
-     *
-     * @return StyleBuilder
-     */
-    public function setFontItalic()
-    {
-        $this->style->setFontItalic();
-
-        return $this;
-    }
-
-    /**
-     * Makes the font underlined.
-     *
-     * @return StyleBuilder
-     */
-    public function setFontUnderline()
-    {
-        $this->style->setFontUnderline();
-
-        return $this;
-    }
-
-    /**
-     * Makes the font struck through.
-     *
-     * @return StyleBuilder
-     */
-    public function setFontStrikethrough()
-    {
-        $this->style->setFontStrikethrough();
-
-        return $this;
-    }
-
-    /**
-     * Sets the font size.
-     *
-     * @param int $fontSize Font size, in pixels
-     *
-     * @return StyleBuilder
-     */
-    public function setFontSize($fontSize)
-    {
-        $this->style->setFontSize($fontSize);
-
-        return $this;
-    }
-
-    /**
-     * Sets the font color.
-     *
-     * @param string $fontColor ARGB color (@see Color)
-     *
-     * @return StyleBuilder
-     */
-    public function setFontColor($fontColor)
-    {
-        $this->style->setFontColor($fontColor);
-
-        return $this;
-    }
-
-    /**
-     * Sets the font name.
-     *
-     * @param string $fontName Name of the font to use
-     *
-     * @return StyleBuilder
-     */
-    public function setFontName($fontName)
-    {
-        $this->style->setFontName($fontName);
-
-        return $this;
-    }
-
-    /**
-     * Makes the text wrap in the cell if requested.
-     *
-     * @param bool $shouldWrap Should the text be wrapped
-     *
-     * @return StyleBuilder
-     */
-    public function setShouldWrapText($shouldWrap = true)
-    {
-        $this->style->setShouldWrapText($shouldWrap);
-
-        return $this;
-    }
-
-    /**
-     * Sets the cell alignment.
-     *
-     * @param string $cellAlignment The cell alignment
-     *
-     * @throws InvalidArgumentException If the given cell alignment is not valid
-     *
-     * @return StyleBuilder
-     */
-    public function setCellAlignment($cellAlignment)
-    {
-        if (!CellAlignment::isValid($cellAlignment)) {
-            throw new InvalidArgumentException('Invalid cell alignment value');
-        }
-
-        $this->style->setCellAlignment($cellAlignment);
-
-        return $this;
-    }
-
-    /**
-     * Set a border.
-     *
-     * @return $this
-     */
-    public function setBorder(Border $border)
-    {
-        $this->style->setBorder($border);
-
-        return $this;
-    }
-
-    /**
-     *  Sets a background color.
-     *
-     * @param string $color ARGB color (@see Color)
-     *
-     * @return StyleBuilder
-     */
-    public function setBackgroundColor($color)
-    {
-        $this->style->setBackgroundColor($color);
-
-        return $this;
-    }
-
-    /**
-     *  Sets a format.
-     *
-     * @param string $format Format
-     *
-     * @return StyleBuilder
-     *
-     * @api
-     */
-    public function setFormat($format)
-    {
-        $this->style->setFormat($format);
-
-        return $this;
-    }
-
-    /**
-     * Set should shrink to fit.
-     *
-     * @param bool $shrinkToFit
-     *
-     * @return StyleBuilder
-     *
-     * @api
-     */
-    public function setShouldShrinkToFit($shrinkToFit = true)
-    {
-        $this->style->setShouldShrinkToFit($shrinkToFit);
-
-        return $this;
-    }
-
-    /**
-     * Returns the configured style. The style is cached and can be reused.
-     *
-     * @return Style
-     */
-    public function build()
-    {
-        return $this->style;
-    }
-}
diff --git a/lib/openspout/src/Writer/Common/Creator/WriterEntityFactory.php b/lib/openspout/src/Writer/Common/Creator/WriterEntityFactory.php
deleted file mode 100644
index da6a43ac2ef..00000000000
--- a/lib/openspout/src/Writer/Common/Creator/WriterEntityFactory.php
+++ /dev/null
@@ -1,121 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\Common\Creator;
-
-use OpenSpout\Common\Entity\Cell;
-use OpenSpout\Common\Entity\Row;
-use OpenSpout\Common\Entity\Style\Style;
-use OpenSpout\Common\Exception\UnsupportedTypeException;
-use OpenSpout\Common\Type;
-use OpenSpout\Writer\WriterInterface;
-
-/**
- * Factory to create external entities.
- */
-class WriterEntityFactory
-{
-    /**
-     * This creates an instance of the appropriate writer, given the type of the file to be written.
-     *
-     * @param string $writerType Type of the writer to instantiate
-     *
-     * @throws \OpenSpout\Common\Exception\UnsupportedTypeException
-     *
-     * @return WriterInterface
-     */
-    public static function createWriter($writerType)
-    {
-        return WriterFactory::createFromType($writerType);
-    }
-
-    /**
-     * This creates an instance of the appropriate writer, given the extension of the file to be written.
-     *
-     * @param string $path The path to the spreadsheet file. Supported extensions are .csv, .ods and .xlsx
-     *
-     * @throws \OpenSpout\Common\Exception\UnsupportedTypeException
-     *
-     * @return WriterInterface
-     */
-    public static function createWriterFromFile(string $path)
-    {
-        return WriterFactory::createFromFile($path);
-    }
-
-    /**
-     * This creates an instance of a CSV writer.
-     *
-     * @return \OpenSpout\Writer\CSV\Writer
-     */
-    public static function createCSVWriter()
-    {
-        try {
-            return WriterFactory::createFromType(Type::CSV);
-        } catch (UnsupportedTypeException $e) {
-            // should never happen
-            return null;
-        }
-    }
-
-    /**
-     * This creates an instance of a XLSX writer.
-     *
-     * @return \OpenSpout\Writer\XLSX\Writer
-     */
-    public static function createXLSXWriter()
-    {
-        try {
-            return WriterFactory::createFromType(Type::XLSX);
-        } catch (UnsupportedTypeException $e) {
-            // should never happen
-            return null;
-        }
-    }
-
-    /**
-     * This creates an instance of a ODS writer.
-     *
-     * @return \OpenSpout\Writer\ODS\Writer
-     */
-    public static function createODSWriter()
-    {
-        try {
-            return WriterFactory::createFromType(Type::ODS);
-        } catch (UnsupportedTypeException $e) {
-            // should never happen
-            return null;
-        }
-    }
-
-    /**
-     * @param Cell[] $cells
-     *
-     * @return Row
-     */
-    public static function createRow(array $cells = [], Style $rowStyle = null)
-    {
-        return new Row($cells, $rowStyle);
-    }
-
-    /**
-     * @return Row
-     */
-    public static function createRowFromArray(array $cellValues = [], Style $rowStyle = null)
-    {
-        $cells = array_map(function ($cellValue) {
-            return new Cell($cellValue);
-        }, $cellValues);
-
-        return new Row($cells, $rowStyle);
-    }
-
-    /**
-     * @param mixed $cellValue
-     *
-     * @return Cell
-     */
-    public static function createCell($cellValue, Style $cellStyle = null)
-    {
-        return new Cell($cellValue, $cellStyle);
-    }
-}
diff --git a/lib/openspout/src/Writer/Common/Creator/WriterFactory.php b/lib/openspout/src/Writer/Common/Creator/WriterFactory.php
index 7c6b53b809c..530633ecab7 100644
--- a/lib/openspout/src/Writer/Common/Creator/WriterFactory.php
+++ b/lib/openspout/src/Writer/Common/Creator/WriterFactory.php
@@ -1,29 +1,20 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Creator;
 
-use OpenSpout\Common\Creator\HelperFactory;
 use OpenSpout\Common\Exception\UnsupportedTypeException;
-use OpenSpout\Common\Helper\GlobalFunctionsHelper;
-use OpenSpout\Common\Type;
-use OpenSpout\Writer\Common\Creator\Style\StyleBuilder;
-use OpenSpout\Writer\CSV\Manager\OptionsManager as CSVOptionsManager;
 use OpenSpout\Writer\CSV\Writer as CSVWriter;
-use OpenSpout\Writer\ODS\Creator\HelperFactory as ODSHelperFactory;
-use OpenSpout\Writer\ODS\Creator\ManagerFactory as ODSManagerFactory;
-use OpenSpout\Writer\ODS\Manager\OptionsManager as ODSOptionsManager;
 use OpenSpout\Writer\ODS\Writer as ODSWriter;
 use OpenSpout\Writer\WriterInterface;
-use OpenSpout\Writer\XLSX\Creator\HelperFactory as XLSXHelperFactory;
-use OpenSpout\Writer\XLSX\Creator\ManagerFactory as XLSXManagerFactory;
-use OpenSpout\Writer\XLSX\Manager\OptionsManager as XLSXOptionsManager;
 use OpenSpout\Writer\XLSX\Writer as XLSXWriter;
 
 /**
  * This factory is used to create writers, based on the type of the file to be read.
  * It supports CSV, XLSX and ODS formats.
  */
-class WriterFactory
+final class WriterFactory
 {
     /**
      * This creates an instance of the appropriate writer, given the extension of the file to be written.
@@ -31,79 +22,16 @@ class WriterFactory
      * @param string $path The path to the spreadsheet file. Supported extensions are .csv,.ods and .xlsx
      *
      * @throws \OpenSpout\Common\Exception\UnsupportedTypeException
-     *
-     * @return WriterInterface
      */
-    public static function createFromFile(string $path)
+    public static function createFromFile(string $path): WriterInterface
     {
         $extension = strtolower(pathinfo($path, PATHINFO_EXTENSION));
 
-        return self::createFromType($extension);
-    }
-
-    /**
-     * This creates an instance of the appropriate writer, given the type of the file to be written.
-     *
-     * @param string $writerType Type of the writer to instantiate
-     *
-     * @throws \OpenSpout\Common\Exception\UnsupportedTypeException
-     *
-     * @return WriterInterface
-     */
-    public static function createFromType($writerType)
-    {
-        switch ($writerType) {
-            case Type::CSV: return self::createCSVWriter();
-
-            case Type::XLSX: return self::createXLSXWriter();
-
-            case Type::ODS: return self::createODSWriter();
-
-            default:
-                throw new UnsupportedTypeException('No writers supporting the given type: '.$writerType);
-        }
-    }
-
-    /**
-     * @return CSVWriter
-     */
-    private static function createCSVWriter()
-    {
-        $optionsManager = new CSVOptionsManager();
-        $globalFunctionsHelper = new GlobalFunctionsHelper();
-
-        $helperFactory = new HelperFactory();
-
-        return new CSVWriter($optionsManager, $globalFunctionsHelper, $helperFactory);
-    }
-
-    /**
-     * @return XLSXWriter
-     */
-    private static function createXLSXWriter()
-    {
-        $styleBuilder = new StyleBuilder();
-        $optionsManager = new XLSXOptionsManager($styleBuilder);
-        $globalFunctionsHelper = new GlobalFunctionsHelper();
-
-        $helperFactory = new XLSXHelperFactory();
-        $managerFactory = new XLSXManagerFactory(new InternalEntityFactory(), $helperFactory);
-
-        return new XLSXWriter($optionsManager, $globalFunctionsHelper, $helperFactory, $managerFactory);
-    }
-
-    /**
-     * @return ODSWriter
-     */
-    private static function createODSWriter()
-    {
-        $styleBuilder = new StyleBuilder();
-        $optionsManager = new ODSOptionsManager($styleBuilder);
-        $globalFunctionsHelper = new GlobalFunctionsHelper();
-
-        $helperFactory = new ODSHelperFactory();
-        $managerFactory = new ODSManagerFactory(new InternalEntityFactory(), $helperFactory);
-
-        return new ODSWriter($optionsManager, $globalFunctionsHelper, $helperFactory, $managerFactory);
+        return match ($extension) {
+            'csv' => new CSVWriter(),
+            'xlsx' => new XLSXWriter(),
+            'ods' => new ODSWriter(),
+            default => throw new UnsupportedTypeException('No writers supporting the given type: '.$extension),
+        };
     }
 }
diff --git a/lib/openspout/src/Writer/Common/Entity/Options.php b/lib/openspout/src/Writer/Common/Entity/Options.php
deleted file mode 100644
index bcf1936e22a..00000000000
--- a/lib/openspout/src/Writer/Common/Entity/Options.php
+++ /dev/null
@@ -1,30 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\Common\Entity;
-
-/**
- * Writers' options holder.
- */
-abstract class Options
-{
-    // CSV specific options
-    public const FIELD_DELIMITER = 'fieldDelimiter';
-    public const FIELD_ENCLOSURE = 'fieldEnclosure';
-    public const SHOULD_ADD_BOM = 'shouldAddBOM';
-
-    // Multisheets options
-    public const TEMP_FOLDER = 'tempFolder';
-    public const DEFAULT_ROW_STYLE = 'defaultRowStyle';
-    public const SHOULD_CREATE_NEW_SHEETS_AUTOMATICALLY = 'shouldCreateNewSheetsAutomatically';
-
-    // XLSX specific options
-    public const SHOULD_USE_INLINE_STRINGS = 'shouldUseInlineStrings';
-
-    // Cell size options
-    public const DEFAULT_COLUMN_WIDTH = 'defaultColumnWidth';
-    public const DEFAULT_ROW_HEIGHT = 'defaultRowHeight';
-    public const COLUMN_WIDTHS = 'columnWidthDefinition';
-
-    // XLSX merge cells
-    public const MERGE_CELLS = 'mergeCells';
-}
diff --git a/lib/openspout/src/Writer/Common/Entity/Sheet.php b/lib/openspout/src/Writer/Common/Entity/Sheet.php
index 1c7ab10e955..fb41a722257 100644
--- a/lib/openspout/src/Writer/Common/Entity/Sheet.php
+++ b/lib/openspout/src/Writer/Common/Entity/Sheet.php
@@ -1,41 +1,52 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Entity;
 
+use OpenSpout\Writer\AutoFilter;
+use OpenSpout\Writer\Common\ColumnWidth;
 use OpenSpout\Writer\Common\Manager\SheetManager;
 use OpenSpout\Writer\XLSX\Entity\SheetView;
 
 /**
  * External representation of a worksheet.
  */
-class Sheet
+final class Sheet
 {
     public const DEFAULT_SHEET_NAME_PREFIX = 'Sheet';
 
-    /** @var int Index of the sheet, based on order in the workbook (zero-based) */
-    private $index;
+    /** @var 0|positive-int Index of the sheet, based on order in the workbook (zero-based) */
+    private int $index;
 
     /** @var string ID of the sheet's associated workbook. Used to restrict sheet name uniqueness enforcement to a single workbook */
-    private $associatedWorkbookId;
+    private string $associatedWorkbookId;
 
     /** @var string Name of the sheet */
-    private $name;
+    private string $name;
 
     /** @var bool Visibility of the sheet */
-    private $isVisible;
+    private bool $isVisible;
 
     /** @var SheetManager Sheet manager */
-    private $sheetManager;
+    private SheetManager $sheetManager;
 
-    /** @var SheetView */
-    private $sheetView;
+    private ?SheetView $sheetView = null;
+
+    /** @var 0|positive-int */
+    private int $writtenRowCount = 0;
+
+    private ?AutoFilter $autoFilter = null;
+
+    /** @var ColumnWidth[] Array of min-max-width arrays */
+    private array $COLUMN_WIDTHS = [];
 
     /**
-     * @param int          $sheetIndex           Index of the sheet, based on order in the workbook (zero-based)
-     * @param string       $associatedWorkbookId ID of the sheet's associated workbook
-     * @param SheetManager $sheetManager         To manage sheets
+     * @param 0|positive-int $sheetIndex           Index of the sheet, based on order in the workbook (zero-based)
+     * @param string         $associatedWorkbookId ID of the sheet's associated workbook
+     * @param SheetManager   $sheetManager         To manage sheets
      */
-    public function __construct($sheetIndex, $associatedWorkbookId, SheetManager $sheetManager)
+    public function __construct(int $sheetIndex, string $associatedWorkbookId, SheetManager $sheetManager)
     {
         $this->index = $sheetIndex;
         $this->associatedWorkbookId = $associatedWorkbookId;
@@ -48,17 +59,14 @@ class Sheet
     }
 
     /**
-     * @return int Index of the sheet, based on order in the workbook (zero-based)
+     * @return 0|positive-int Index of the sheet, based on order in the workbook (zero-based)
      */
-    public function getIndex()
+    public function getIndex(): int
     {
         return $this->index;
     }
 
-    /**
-     * @return string
-     */
-    public function getAssociatedWorkbookId()
+    public function getAssociatedWorkbookId(): string
     {
         return $this->associatedWorkbookId;
     }
@@ -66,7 +74,7 @@ class Sheet
     /**
      * @return string Name of the sheet
      */
-    public function getName()
+    public function getName(): string
     {
         return $this->name;
     }
@@ -81,10 +89,8 @@ class Sheet
      * @param string $name Name of the sheet
      *
      * @throws \OpenSpout\Writer\Exception\InvalidSheetNameException if the sheet's name is invalid
-     *
-     * @return Sheet
      */
-    public function setName($name)
+    public function setName(string $name): self
     {
         $this->sheetManager->throwIfNameIsInvalid($name, $this);
 
@@ -98,40 +104,105 @@ class Sheet
     /**
      * @return bool isVisible Visibility of the sheet
      */
-    public function isVisible()
+    public function isVisible(): bool
     {
         return $this->isVisible;
     }
 
     /**
      * @param bool $isVisible Visibility of the sheet
-     *
-     * @return Sheet
      */
-    public function setIsVisible($isVisible)
+    public function setIsVisible(bool $isVisible): self
     {
         $this->isVisible = $isVisible;
 
         return $this;
     }
 
+    /**
+     * @return $this
+     */
+    public function setSheetView(SheetView $sheetView): self
+    {
+        $this->sheetView = $sheetView;
+
+        return $this;
+    }
+
     public function getSheetView(): ?SheetView
     {
         return $this->sheetView;
     }
 
+    /**
+     * @internal
+     */
+    public function incrementWrittenRowCount(): void
+    {
+        ++$this->writtenRowCount;
+    }
+
+    /**
+     * @return 0|positive-int
+     */
+    public function getWrittenRowCount(): int
+    {
+        return $this->writtenRowCount;
+    }
+
     /**
      * @return $this
      */
-    public function setSheetView(SheetView $sheetView)
+    public function setAutoFilter(?AutoFilter $autoFilter): self
     {
-        $this->sheetView = $sheetView;
+        $this->autoFilter = $autoFilter;
 
         return $this;
     }
 
-    public function hasSheetView(): bool
+    public function getAutoFilter(): ?AutoFilter
     {
-        return $this->sheetView instanceof SheetView;
+        return $this->autoFilter;
+    }
+
+    /**
+     * @param positive-int ...$columns One or more columns with this width
+     */
+    public function setColumnWidth(float $width, int ...$columns): void
+    {
+        // Gather sequences
+        $sequence = [];
+        foreach ($columns as $column) {
+            $sequenceLength = \count($sequence);
+            if ($sequenceLength > 0) {
+                $previousValue = $sequence[$sequenceLength - 1];
+                if ($column !== $previousValue + 1) {
+                    $this->setColumnWidthForRange($width, $sequence[0], $previousValue);
+                    $sequence = [];
+                }
+            }
+            $sequence[] = $column;
+        }
+        $this->setColumnWidthForRange($width, $sequence[0], $sequence[\count($sequence) - 1]);
+    }
+
+    /**
+     * @param float        $width The width to set
+     * @param positive-int $start First column index of the range
+     * @param positive-int $end   Last column index of the range
+     */
+    public function setColumnWidthForRange(float $width, int $start, int $end): void
+    {
+        $this->COLUMN_WIDTHS[] = new ColumnWidth($start, $end, $width);
+    }
+
+    /**
+     * @internal
+     *
+     * @return ColumnWidth[]
+     */
+    public function getColumnWidths(): array
+    {
+        return $this->COLUMN_WIDTHS;
     }
 }
diff --git a/lib/openspout/src/Writer/Common/Entity/Workbook.php b/lib/openspout/src/Writer/Common/Entity/Workbook.php
index 152ded82b8c..e179c513b76 100644
--- a/lib/openspout/src/Writer/Common/Entity/Workbook.php
+++ b/lib/openspout/src/Writer/Common/Entity/Workbook.php
@@ -1,17 +1,19 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Entity;
 
 /**
  * Entity describing a workbook.
  */
-class Workbook
+final class Workbook
 {
     /** @var Worksheet[] List of the workbook's sheets */
-    private $worksheets = [];
+    private array $worksheets = [];
 
     /** @var string Timestamp based unique ID identifying the workbook */
-    private $internalId;
+    private string $internalId;
 
     /**
      * Workbook constructor.
@@ -24,7 +26,7 @@ class Workbook
     /**
      * @return Worksheet[]
      */
-    public function getWorksheets()
+    public function getWorksheets(): array
     {
         return $this->worksheets;
     }
@@ -32,15 +34,12 @@ class Workbook
     /**
      * @param Worksheet[] $worksheets
      */
-    public function setWorksheets($worksheets)
+    public function setWorksheets(array $worksheets): void
     {
         $this->worksheets = $worksheets;
     }
 
-    /**
-     * @return string
-     */
-    public function getInternalId()
+    public function getInternalId(): string
     {
         return $this->internalId;
     }
diff --git a/lib/openspout/src/Writer/Common/Entity/Worksheet.php b/lib/openspout/src/Writer/Common/Entity/Worksheet.php
index 0263429e746..6fc6a2f659c 100644
--- a/lib/openspout/src/Writer/Common/Entity/Worksheet.php
+++ b/lib/openspout/src/Writer/Common/Entity/Worksheet.php
@@ -1,49 +1,42 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Entity;
 
 /**
  * Entity describing a Worksheet.
  */
-class Worksheet
+final class Worksheet
 {
     /** @var string Path to the XML file that will contain the sheet data */
-    private $filePath;
+    private string $filePath;
 
     /** @var null|resource Pointer to the sheet data file (e.g. xl/worksheets/sheet1.xml) */
     private $filePointer;
 
     /** @var Sheet The "external" sheet */
-    private $externalSheet;
+    private Sheet $externalSheet;
 
     /** @var int Maximum number of columns among all the written rows */
-    private $maxNumColumns;
+    private int $maxNumColumns;
 
     /** @var int Index of the last written row */
-    private $lastWrittenRowIndex;
-
-    /** @var bool has the sheet data header been written */
-    private $sheetDataStarted = false;
+    private int $lastWrittenRowIndex;
 
     /**
      * Worksheet constructor.
-     *
-     * @param string $worksheetFilePath
      */
-    public function __construct($worksheetFilePath, Sheet $externalSheet)
+    public function __construct(string $worksheetFilePath, Sheet $externalSheet)
     {
         $this->filePath = $worksheetFilePath;
         $this->filePointer = null;
         $this->externalSheet = $externalSheet;
         $this->maxNumColumns = 0;
         $this->lastWrittenRowIndex = 0;
-        $this->sheetDataStarted = false;
     }
 
-    /**
-     * @return string
-     */
-    public function getFilePath()
+    public function getFilePath(): string
     {
         return $this->filePath;
     }
@@ -53,53 +46,40 @@ class Worksheet
      */
     public function getFilePointer()
     {
+        \assert(null !== $this->filePointer);
+
         return $this->filePointer;
     }
 
     /**
      * @param resource $filePointer
      */
-    public function setFilePointer($filePointer)
+    public function setFilePointer($filePointer): void
     {
         $this->filePointer = $filePointer;
     }
 
-    /**
-     * @return Sheet
-     */
-    public function getExternalSheet()
+    public function getExternalSheet(): Sheet
     {
         return $this->externalSheet;
     }
 
-    /**
-     * @return int
-     */
-    public function getMaxNumColumns()
+    public function getMaxNumColumns(): int
     {
         return $this->maxNumColumns;
     }
 
-    /**
-     * @param int $maxNumColumns
-     */
-    public function setMaxNumColumns($maxNumColumns)
+    public function setMaxNumColumns(int $maxNumColumns): void
     {
         $this->maxNumColumns = $maxNumColumns;
     }
 
-    /**
-     * @return int
-     */
-    public function getLastWrittenRowIndex()
+    public function getLastWrittenRowIndex(): int
     {
         return $this->lastWrittenRowIndex;
     }
 
-    /**
-     * @param int $lastWrittenRowIndex
-     */
-    public function setLastWrittenRowIndex($lastWrittenRowIndex)
+    public function setLastWrittenRowIndex(int $lastWrittenRowIndex): void
     {
         $this->lastWrittenRowIndex = $lastWrittenRowIndex;
     }
@@ -107,25 +87,9 @@ class Worksheet
     /**
      * @return int The ID of the worksheet
      */
-    public function getId()
+    public function getId(): int
     {
         // sheet index is zero-based, while ID is 1-based
         return $this->externalSheet->getIndex() + 1;
     }
-
-    /**
-     * @return bool
-     */
-    public function getSheetDataStarted()
-    {
-        return $this->sheetDataStarted;
-    }
-
-    /**
-     * @param bool $sheetDataStarted
-     */
-    public function setSheetDataStarted($sheetDataStarted)
-    {
-        $this->sheetDataStarted = $sheetDataStarted;
-    }
 }
diff --git a/lib/openspout/src/Writer/Common/Helper/CellHelper.php b/lib/openspout/src/Writer/Common/Helper/CellHelper.php
index 400e82ca2e3..e70978d8193 100644
--- a/lib/openspout/src/Writer/Common/Helper/CellHelper.php
+++ b/lib/openspout/src/Writer/Common/Helper/CellHelper.php
@@ -1,14 +1,16 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Helper;
 
 /**
- * This class provides helper functions when working with cells.
+ * @internal
  */
-class CellHelper
+final class CellHelper
 {
-    /** @var array Cache containing the mapping column index => column letters */
-    private static $columnIndexToColumnLettersCache = [];
+    /** @var array<int, string> Cache containing the mapping column index => column letters */
+    private static array $columnIndexToColumnLettersCache = [];
 
     /**
      * Returns the column letters (base 26) associated to the base 10 column index.
@@ -20,7 +22,7 @@ class CellHelper
      *
      * @return string The associated cell index ('A', 'BC', ...)
      */
-    public static function getColumnLettersFromColumnIndex($columnIndexZeroBased)
+    public static function getColumnLettersFromColumnIndex(int $columnIndexZeroBased): string
     {
         $originalColumnIndex = $columnIndexZeroBased;
 
diff --git a/lib/openspout/src/Writer/Common/Helper/FileSystemWithRootFolderHelperInterface.php b/lib/openspout/src/Writer/Common/Helper/FileSystemWithRootFolderHelperInterface.php
index f571ebf1104..afd365b12cc 100644
--- a/lib/openspout/src/Writer/Common/Helper/FileSystemWithRootFolderHelperInterface.php
+++ b/lib/openspout/src/Writer/Common/Helper/FileSystemWithRootFolderHelperInterface.php
@@ -1,12 +1,13 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Helper;
 
 use OpenSpout\Common\Helper\FileSystemHelperInterface;
 
 /**
- * This interface describes helper functions to help with the file system operations
- * like files/folders creation & deletion.
+ * @internal
  */
 interface FileSystemWithRootFolderHelperInterface extends FileSystemHelperInterface
 {
@@ -15,10 +16,9 @@ interface FileSystemWithRootFolderHelperInterface extends FileSystemHelperInterf
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create at least one of the base folders
      */
-    public function createBaseFilesAndFolders();
+    public function createBaseFilesAndFolders(): void;
 
-    /**
-     * @return string
-     */
-    public function getRootFolder();
+    public function getRootFolder(): string;
+
+    public function getSheetsContentTempFolder(): string;
 }
diff --git a/lib/openspout/src/Writer/Common/Helper/ZipHelper.php b/lib/openspout/src/Writer/Common/Helper/ZipHelper.php
index 073b3d28cc5..1288d6abf9e 100644
--- a/lib/openspout/src/Writer/Common/Helper/ZipHelper.php
+++ b/lib/openspout/src/Writer/Common/Helper/ZipHelper.php
@@ -1,54 +1,48 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Helper;
 
-use OpenSpout\Writer\Common\Creator\InternalEntityFactory;
+use RecursiveDirectoryIterator;
+use RecursiveIteratorIterator;
+use SplFileInfo;
+use ZipArchive;
 
 /**
- * This class provides helper functions to create zip files.
+ * @internal
  */
-class ZipHelper
+final class ZipHelper
 {
     public const ZIP_EXTENSION = '.zip';
 
-    /** Controls what to do when trying to add an existing file */
+    /**
+     * Controls what to do when trying to add an existing file.
+     */
     public const EXISTING_FILES_SKIP = 'skip';
     public const EXISTING_FILES_OVERWRITE = 'overwrite';
 
-    /** @var InternalEntityFactory Factory to create entities */
-    private $entityFactory;
-
-    /**
-     * @param InternalEntityFactory $entityFactory Factory to create entities
-     */
-    public function __construct($entityFactory)
-    {
-        $this->entityFactory = $entityFactory;
-    }
-
     /**
      * Returns a new ZipArchive instance pointing at the given path.
      *
      * @param string $tmpFolderPath Path of the temp folder where the zip file will be created
-     *
-     * @return \ZipArchive
      */
-    public function createZip($tmpFolderPath)
+    public function createZip(string $tmpFolderPath): ZipArchive
     {
-        $zip = $this->entityFactory->createZipArchive();
+        $zip = new ZipArchive();
         $zipFilePath = $tmpFolderPath.self::ZIP_EXTENSION;
 
-        $zip->open($zipFilePath, \ZipArchive::CREATE | \ZipArchive::OVERWRITE);
+        $zip->open($zipFilePath, ZipArchive::CREATE | ZipArchive::OVERWRITE);
 
         return $zip;
     }
 
     /**
-     * @param \ZipArchive $zip An opened zip archive object
+     * @param ZipArchive $zip An opened zip archive object
      *
      * @return string Path where the zip file of the given folder will be created
      */
-    public function getZipFilePath(\ZipArchive $zip)
+    public function getZipFilePath(ZipArchive $zip): string
     {
         return $zip->filename;
     }
@@ -61,19 +55,19 @@ class ZipHelper
      *   addFileToArchive($zip, '/tmp/xlsx/foo', 'bar/baz.xml');
      *   => will add the file located at '/tmp/xlsx/foo/bar/baz.xml' in the archive, but only as 'bar/baz.xml'
      *
-     * @param \ZipArchive $zip              An opened zip archive object
-     * @param string      $rootFolderPath   path of the root folder that will be ignored in the archive tree
-     * @param string      $localFilePath    Path of the file to be added, under the root folder
-     * @param string      $existingFileMode Controls what to do when trying to add an existing file
+     * @param ZipArchive $zip              An opened zip archive object
+     * @param string     $rootFolderPath   path of the root folder that will be ignored in the archive tree
+     * @param string     $localFilePath    Path of the file to be added, under the root folder
+     * @param string     $existingFileMode Controls what to do when trying to add an existing file
      */
-    public function addFileToArchive($zip, $rootFolderPath, $localFilePath, $existingFileMode = self::EXISTING_FILES_OVERWRITE)
+    public function addFileToArchive(ZipArchive $zip, string $rootFolderPath, string $localFilePath, string $existingFileMode = self::EXISTING_FILES_OVERWRITE): void
     {
         $this->addFileToArchiveWithCompressionMethod(
             $zip,
             $rootFolderPath,
             $localFilePath,
             $existingFileMode,
-            \ZipArchive::CM_DEFAULT
+            ZipArchive::CM_DEFAULT
         );
     }
 
@@ -85,42 +79,37 @@ class ZipHelper
      *   addUncompressedFileToArchive($zip, '/tmp/xlsx/foo', 'bar/baz.xml');
      *   => will add the file located at '/tmp/xlsx/foo/bar/baz.xml' in the archive, but only as 'bar/baz.xml'
      *
-     * @param \ZipArchive $zip              An opened zip archive object
-     * @param string      $rootFolderPath   path of the root folder that will be ignored in the archive tree
-     * @param string      $localFilePath    Path of the file to be added, under the root folder
-     * @param string      $existingFileMode Controls what to do when trying to add an existing file
+     * @param ZipArchive $zip              An opened zip archive object
+     * @param string     $rootFolderPath   path of the root folder that will be ignored in the archive tree
+     * @param string     $localFilePath    Path of the file to be added, under the root folder
+     * @param string     $existingFileMode Controls what to do when trying to add an existing file
      */
-    public function addUncompressedFileToArchive($zip, $rootFolderPath, $localFilePath, $existingFileMode = self::EXISTING_FILES_OVERWRITE)
+    public function addUncompressedFileToArchive(ZipArchive $zip, string $rootFolderPath, string $localFilePath, string $existingFileMode = self::EXISTING_FILES_OVERWRITE): void
     {
         $this->addFileToArchiveWithCompressionMethod(
             $zip,
             $rootFolderPath,
             $localFilePath,
             $existingFileMode,
-            \ZipArchive::CM_STORE
+            ZipArchive::CM_STORE
         );
     }
 
     /**
-     * @return bool Whether it is possible to choose the desired compression method to be used
+     * @param ZipArchive $zip              An opened zip archive object
+     * @param string     $folderPath       Path to the folder to be zipped
+     * @param string     $existingFileMode Controls what to do when trying to add an existing file
      */
-    public static function canChooseCompressionMethod()
-    {
-        // setCompressionName() is a PHP7+ method...
-        return method_exists(new \ZipArchive(), 'setCompressionName');
-    }
-
-    /**
-     * @param \ZipArchive $zip              An opened zip archive object
-     * @param string      $folderPath       Path to the folder to be zipped
-     * @param string      $existingFileMode Controls what to do when trying to add an existing file
-     */
-    public function addFolderToArchive($zip, $folderPath, $existingFileMode = self::EXISTING_FILES_OVERWRITE)
+    public function addFolderToArchive(ZipArchive $zip, string $folderPath, string $existingFileMode = self::EXISTING_FILES_OVERWRITE): void
     {
         $folderRealPath = $this->getNormalizedRealPath($folderPath).'/';
-        $itemIterator = new \RecursiveIteratorIterator(new \RecursiveDirectoryIterator($folderPath, \RecursiveDirectoryIterator::SKIP_DOTS), \RecursiveIteratorIterator::SELF_FIRST);
+        $itemIterator = new RecursiveIteratorIterator(
+            new RecursiveDirectoryIterator($folderPath, RecursiveDirectoryIterator::SKIP_DOTS),
+            RecursiveIteratorIterator::SELF_FIRST
+        );
 
         foreach ($itemIterator as $itemInfo) {
+            \assert($itemInfo instanceof SplFileInfo);
             $itemRealPath = $this->getNormalizedRealPath($itemInfo->getPathname());
             $itemLocalPath = str_replace($folderRealPath, '', $itemRealPath);
 
@@ -133,10 +122,10 @@ class ZipHelper
     /**
      * Closes the archive and copies it into the given stream.
      *
-     * @param \ZipArchive $zip           An opened zip archive object
-     * @param resource    $streamPointer Pointer to the stream to copy the zip
+     * @param ZipArchive $zip           An opened zip archive object
+     * @param resource   $streamPointer Pointer to the stream to copy the zip
      */
-    public function closeArchiveAndCopyToStream($zip, $streamPointer)
+    public function closeArchiveAndCopyToStream(ZipArchive $zip, $streamPointer): void
     {
         $zipFilePath = $zip->filename;
         $zip->close();
@@ -152,32 +141,27 @@ class ZipHelper
      *   addUncompressedFileToArchive($zip, '/tmp/xlsx/foo', 'bar/baz.xml');
      *   => will add the file located at '/tmp/xlsx/foo/bar/baz.xml' in the archive, but only as 'bar/baz.xml'
      *
-     * @param \ZipArchive $zip               An opened zip archive object
-     * @param string      $rootFolderPath    path of the root folder that will be ignored in the archive tree
-     * @param string      $localFilePath     Path of the file to be added, under the root folder
-     * @param string      $existingFileMode  Controls what to do when trying to add an existing file
-     * @param int         $compressionMethod The compression method
+     * @param ZipArchive $zip               An opened zip archive object
+     * @param string     $rootFolderPath    path of the root folder that will be ignored in the archive tree
+     * @param string     $localFilePath     Path of the file to be added, under the root folder
+     * @param string     $existingFileMode  Controls what to do when trying to add an existing file
+     * @param int        $compressionMethod The compression method
      */
-    protected function addFileToArchiveWithCompressionMethod($zip, $rootFolderPath, $localFilePath, $existingFileMode, $compressionMethod)
+    private function addFileToArchiveWithCompressionMethod(ZipArchive $zip, string $rootFolderPath, string $localFilePath, string $existingFileMode, int $compressionMethod): void
     {
-        if (!$this->shouldSkipFile($zip, $localFilePath, $existingFileMode)) {
-            $normalizedFullFilePath = $this->getNormalizedRealPath($rootFolderPath.'/'.$localFilePath);
-            $zip->addFile($normalizedFullFilePath, $localFilePath);
+        $normalizedLocalFilePath = str_replace('\\', '/', $localFilePath);
+        if (!$this->shouldSkipFile($zip, $normalizedLocalFilePath, $existingFileMode)) {
+            $normalizedFullFilePath = $this->getNormalizedRealPath($rootFolderPath.'/'.$normalizedLocalFilePath);
+            $zip->addFile($normalizedFullFilePath, $normalizedLocalFilePath);
 
-            if (self::canChooseCompressionMethod()) {
-                $zip->setCompressionName($localFilePath, $compressionMethod);
-            }
+            $zip->setCompressionName($normalizedLocalFilePath, $compressionMethod);
         }
     }
 
     /**
-     * @param \ZipArchive $zip
-     * @param string      $itemLocalPath
-     * @param string      $existingFileMode
-     *
      * @return bool Whether the file should be added to the archive or skipped
      */
-    protected function shouldSkipFile($zip, $itemLocalPath, $existingFileMode)
+    private function shouldSkipFile(ZipArchive $zip, string $itemLocalPath, string $existingFileMode): bool
     {
         // Skip files if:
         //   - EXISTING_FILES_SKIP mode chosen
@@ -192,9 +176,10 @@ class ZipHelper
      *
      * @return string Normalized and canonicalized path
      */
-    protected function getNormalizedRealPath($path)
+    private function getNormalizedRealPath(string $path): string
     {
         $realPath = realpath($path);
+        \assert(false !== $realPath);
 
         return str_replace(\DIRECTORY_SEPARATOR, '/', $realPath);
     }
@@ -205,9 +190,10 @@ class ZipHelper
      * @param string   $zipFilePath Path of the zip file
      * @param resource $pointer     Pointer to the stream to copy the zip
      */
-    protected function copyZipToStream($zipFilePath, $pointer)
+    private function copyZipToStream(string $zipFilePath, $pointer): void
     {
         $zipFilePointer = fopen($zipFilePath, 'r');
+        \assert(false !== $zipFilePointer);
         stream_copy_to_stream($zipFilePointer, $pointer);
         fclose($zipFilePointer);
     }
diff --git a/lib/openspout/src/Writer/Common/Manager/WorkbookManagerAbstract.php b/lib/openspout/src/Writer/Common/Manager/AbstractWorkbookManager.php
similarity index 60%
rename from lib/openspout/src/Writer/Common/Manager/WorkbookManagerAbstract.php
rename to lib/openspout/src/Writer/Common/Manager/AbstractWorkbookManager.php
index 8ffd7e91c67..3411b140bb3 100644
--- a/lib/openspout/src/Writer/Common/Manager/WorkbookManagerAbstract.php
+++ b/lib/openspout/src/Writer/Common/Manager/AbstractWorkbookManager.php
@@ -1,13 +1,13 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Manager;
 
 use OpenSpout\Common\Entity\Row;
 use OpenSpout\Common\Exception\IOException;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Writer\Common\Creator\InternalEntityFactory;
-use OpenSpout\Writer\Common\Creator\ManagerFactoryInterface;
-use OpenSpout\Writer\Common\Entity\Options;
+use OpenSpout\Common\Helper\StringHelper;
+use OpenSpout\Writer\Common\AbstractOptions;
 use OpenSpout\Writer\Common\Entity\Sheet;
 use OpenSpout\Writer\Common\Entity\Workbook;
 use OpenSpout\Writer\Common\Entity\Worksheet;
@@ -17,63 +17,43 @@ use OpenSpout\Writer\Common\Manager\Style\StyleMerger;
 use OpenSpout\Writer\Exception\SheetNotFoundException;
 
 /**
- * Abstract workbook manager, providing the generic interfaces to work with workbook.
+ * @internal
  */
-abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
+abstract class AbstractWorkbookManager implements WorkbookManagerInterface
 {
-    /** @var null|Workbook The workbook to manage */
-    protected $workbook;
-
-    /** @var OptionsManagerInterface */
-    protected $optionsManager;
-
-    /** @var WorksheetManagerInterface */
-    protected $worksheetManager;
+    protected WorksheetManagerInterface $worksheetManager;
 
     /** @var StyleManagerInterface Manages styles */
-    protected $styleManager;
-
-    /** @var StyleMerger Helper to merge styles */
-    protected $styleMerger;
+    protected StyleManagerInterface $styleManager;
 
     /** @var FileSystemWithRootFolderHelperInterface Helper to perform file system operations */
-    protected $fileSystemHelper;
+    protected FileSystemWithRootFolderHelperInterface $fileSystemHelper;
 
-    /** @var InternalEntityFactory Factory to create entities */
-    protected $entityFactory;
+    protected AbstractOptions $options;
 
-    /** @var ManagerFactoryInterface Factory to create managers */
-    protected $managerFactory;
+    /** @var Workbook The workbook to manage */
+    private Workbook $workbook;
+
+    /** @var StyleMerger Helper to merge styles */
+    private StyleMerger $styleMerger;
 
     /** @var Worksheet The worksheet where data will be written to */
-    protected $currentWorksheet;
+    private Worksheet $currentWorksheet;
 
     public function __construct(
         Workbook $workbook,
-        OptionsManagerInterface $optionsManager,
+        AbstractOptions $options,
         WorksheetManagerInterface $worksheetManager,
         StyleManagerInterface $styleManager,
         StyleMerger $styleMerger,
-        FileSystemWithRootFolderHelperInterface $fileSystemHelper,
-        InternalEntityFactory $entityFactory,
-        ManagerFactoryInterface $managerFactory
+        FileSystemWithRootFolderHelperInterface $fileSystemHelper
     ) {
         $this->workbook = $workbook;
-        $this->optionsManager = $optionsManager;
+        $this->options = $options;
         $this->worksheetManager = $worksheetManager;
         $this->styleManager = $styleManager;
         $this->styleMerger = $styleMerger;
         $this->fileSystemHelper = $fileSystemHelper;
-        $this->entityFactory = $entityFactory;
-        $this->managerFactory = $managerFactory;
-    }
-
-    /**
-     * @return null|Workbook
-     */
-    public function getWorkbook()
-    {
-        return $this->workbook;
     }
 
     /**
@@ -82,7 +62,7 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
      *
      * @return Worksheet The created sheet
      */
-    public function addNewSheetAndMakeItCurrent()
+    final public function addNewSheetAndMakeItCurrent(): Worksheet
     {
         $worksheet = $this->addNewSheet();
         $this->setCurrentWorksheet($worksheet);
@@ -93,7 +73,7 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
     /**
      * @return Worksheet[] All the workbook's sheets
      */
-    public function getWorksheets()
+    final public function getWorksheets(): array
     {
         return $this->workbook->getWorksheets();
     }
@@ -103,21 +83,11 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
      *
      * @return Worksheet The current sheet
      */
-    public function getCurrentWorksheet()
+    final public function getCurrentWorksheet(): Worksheet
     {
         return $this->currentWorksheet;
     }
 
-    /**
-     * Starts the current sheet and opens the file pointer.
-     *
-     * @throws IOException
-     */
-    public function startCurrentSheet()
-    {
-        $this->worksheetManager->startSheet($this->getCurrentWorksheet());
-    }
-
     /**
      * Sets the given sheet as the current one. New data will be written to this sheet.
      * The writing will resume where it stopped (i.e. data won't be truncated).
@@ -126,7 +96,7 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
      *
      * @throws SheetNotFoundException If the given sheet does not exist in the workbook
      */
-    public function setCurrentSheet(Sheet $sheet)
+    final public function setCurrentSheet(Sheet $sheet): void
     {
         $worksheet = $this->getWorksheetFromExternalSheet($sheet);
         if (null !== $worksheet) {
@@ -146,51 +116,19 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
      * @throws IOException                                          If trying to create a new sheet and unable to open the sheet for writing
      * @throws \OpenSpout\Common\Exception\InvalidArgumentException
      */
-    public function addRowToCurrentWorksheet(Row $row)
+    final public function addRowToCurrentWorksheet(Row $row): void
     {
         $currentWorksheet = $this->getCurrentWorksheet();
-        $hasReachedMaxRows = $this->hasCurrentWorksheetReachedMaxRows();
-
-        // if we reached the maximum number of rows for the current sheet...
-        if ($hasReachedMaxRows) {
-            // ... continue writing in a new sheet if option set
-            if ($this->optionsManager->getOption(Options::SHOULD_CREATE_NEW_SHEETS_AUTOMATICALLY)) {
-                $currentWorksheet = $this->addNewSheetAndMakeItCurrent();
-
-                $this->addRowToWorksheet($currentWorksheet, $row);
+        if ($this->hasCurrentWorksheetReachedMaxRows()) {
+            if (!$this->options->SHOULD_CREATE_NEW_SHEETS_AUTOMATICALLY) {
+                return;
             }
-            // otherwise, do nothing as the data won't be written anyways
-        } else {
-            $this->addRowToWorksheet($currentWorksheet, $row);
+
+            $currentWorksheet = $this->addNewSheetAndMakeItCurrent();
         }
-    }
 
-    public function setDefaultColumnWidth(float $width)
-    {
-        $this->worksheetManager->setDefaultColumnWidth($width);
-    }
-
-    public function setDefaultRowHeight(float $height)
-    {
-        $this->worksheetManager->setDefaultRowHeight($height);
-    }
-
-    /**
-     * @param int ...$columns One or more columns with this width
-     */
-    public function setColumnWidth(float $width, ...$columns)
-    {
-        $this->worksheetManager->setColumnWidth($width, ...$columns);
-    }
-
-    /**
-     * @param float $width The width to set
-     * @param int   $start First column index of the range
-     * @param int   $end   Last column index of the range
-     */
-    public function setColumnWidthForRange(float $width, int $start, int $end)
-    {
-        $this->worksheetManager->setColumnWidthForRange($width, $start, $end);
+        $this->addRowToWorksheet($currentWorksheet, $row);
+        $currentWorksheet->getExternalSheet()->incrementWrittenRowCount();
     }
 
     /**
@@ -200,7 +138,7 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
      *
      * @param resource $finalFilePointer Pointer to the spreadsheet that will be created
      */
-    public function close($finalFilePointer)
+    final public function close($finalFilePointer): void
     {
         $this->closeAllWorksheets();
         $this->closeRemainingObjects();
@@ -211,17 +149,12 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
     /**
      * @return int Maximum number of rows/columns a sheet can contain
      */
-    abstract protected function getMaxRowsPerWorksheet();
-
-    /**
-     * @return string The file path where the data for the given sheet will be stored
-     */
-    abstract protected function getWorksheetFilePath(Sheet $sheet);
+    abstract protected function getMaxRowsPerWorksheet(): int;
 
     /**
      * Closes custom objects that are still opened.
      */
-    protected function closeRemainingObjects()
+    protected function closeRemainingObjects(): void
     {
         // do nothing by default
     }
@@ -231,12 +164,22 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
      *
      * @param resource $finalFilePointer Pointer to the spreadsheet that will be created
      */
-    abstract protected function writeAllFilesToDiskAndZipThem($finalFilePointer);
+    abstract protected function writeAllFilesToDiskAndZipThem($finalFilePointer): void;
+
+    /**
+     * @return string The file path where the data for the given sheet will be stored
+     */
+    private function getWorksheetFilePath(Sheet $sheet): string
+    {
+        $sheetsContentTempFolder = $this->fileSystemHelper->getSheetsContentTempFolder();
+
+        return $sheetsContentTempFolder.\DIRECTORY_SEPARATOR.'sheet'.(1 + $sheet->getIndex()).'.xml';
+    }
 
     /**
      * Deletes the root folder created in the temp folder and all its contents.
      */
-    protected function cleanupTempFolder()
+    private function cleanupTempFolder(): void
     {
         $rootFolder = $this->fileSystemHelper->getRootFolder();
         $this->fileSystemHelper->deleteFolderRecursively($rootFolder);
@@ -245,20 +188,20 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
     /**
      * Creates a new sheet in the workbook. The current sheet remains unchanged.
      *
-     * @throws \OpenSpout\Common\Exception\IOException If unable to open the sheet for writing
-     *
      * @return Worksheet The created sheet
+     *
+     * @throws \OpenSpout\Common\Exception\IOException If unable to open the sheet for writing
      */
-    private function addNewSheet()
+    private function addNewSheet(): Worksheet
     {
         $worksheets = $this->getWorksheets();
 
         $newSheetIndex = \count($worksheets);
-        $sheetManager = $this->managerFactory->createSheetManager();
-        $sheet = $this->entityFactory->createSheet($newSheetIndex, $this->workbook->getInternalId(), $sheetManager);
+        $sheetManager = new SheetManager(StringHelper::factory());
+        $sheet = new Sheet($newSheetIndex, $this->workbook->getInternalId(), $sheetManager);
 
         $worksheetFilePath = $this->getWorksheetFilePath($sheet);
-        $worksheet = $this->entityFactory->createWorksheet($worksheetFilePath, $sheet);
+        $worksheet = new Worksheet($worksheetFilePath, $sheet);
 
         $this->worksheetManager->startSheet($worksheet);
 
@@ -268,10 +211,7 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
         return $worksheet;
     }
 
-    /**
-     * @param Worksheet $worksheet
-     */
-    private function setCurrentWorksheet($worksheet)
+    private function setCurrentWorksheet(Worksheet $worksheet): void
     {
         $this->currentWorksheet = $worksheet;
     }
@@ -279,11 +219,9 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
     /**
      * Returns the worksheet associated to the given external sheet.
      *
-     * @param Sheet $sheet
-     *
      * @return null|Worksheet the worksheet associated to the given external sheet or null if not found
      */
-    private function getWorksheetFromExternalSheet($sheet)
+    private function getWorksheetFromExternalSheet(Sheet $sheet): ?Worksheet
     {
         $worksheetFound = null;
 
@@ -301,7 +239,7 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
     /**
      * @return bool whether the current worksheet has reached the maximum number of rows per sheet
      */
-    private function hasCurrentWorksheetReachedMaxRows()
+    private function hasCurrentWorksheetReachedMaxRows(): bool
     {
         $currentWorksheet = $this->getCurrentWorksheet();
 
@@ -317,7 +255,7 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
      * @throws IOException
      * @throws \OpenSpout\Common\Exception\InvalidArgumentException
      */
-    private function addRowToWorksheet(Worksheet $worksheet, Row $row)
+    private function addRowToWorksheet(Worksheet $worksheet, Row $row): void
     {
         $this->applyDefaultRowStyle($row);
         $this->worksheetManager->addRow($worksheet, $row);
@@ -328,20 +266,19 @@ abstract class WorkbookManagerAbstract implements WorkbookManagerInterface
         $worksheet->setMaxNumColumns(max($currentMaxNumColumns, $cellsCount));
     }
 
-    private function applyDefaultRowStyle(Row $row)
+    private function applyDefaultRowStyle(Row $row): void
     {
-        $defaultRowStyle = $this->optionsManager->getOption(Options::DEFAULT_ROW_STYLE);
-
-        if (null !== $defaultRowStyle) {
-            $mergedStyle = $this->styleMerger->merge($row->getStyle(), $defaultRowStyle);
-            $row->setStyle($mergedStyle);
-        }
+        $mergedStyle = $this->styleMerger->merge(
+            $row->getStyle(),
+            $this->options->DEFAULT_ROW_STYLE
+        );
+        $row->setStyle($mergedStyle);
     }
 
     /**
      * Closes all workbook's associated sheets.
      */
-    private function closeAllWorksheets()
+    private function closeAllWorksheets(): void
     {
         $worksheets = $this->getWorksheets();
 
diff --git a/lib/openspout/src/Writer/Common/Manager/CellManager.php b/lib/openspout/src/Writer/Common/Manager/CellManager.php
deleted file mode 100644
index 5ce70d4b2b4..00000000000
--- a/lib/openspout/src/Writer/Common/Manager/CellManager.php
+++ /dev/null
@@ -1,29 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\Common\Manager;
-
-use OpenSpout\Common\Entity\Cell;
-use OpenSpout\Common\Entity\Style\Style;
-use OpenSpout\Writer\Common\Manager\Style\StyleMerger;
-
-class CellManager
-{
-    /**
-     * @var StyleMerger
-     */
-    protected $styleMerger;
-
-    public function __construct(StyleMerger $styleMerger)
-    {
-        $this->styleMerger = $styleMerger;
-    }
-
-    /**
-     * Merges a Style into a cell's Style.
-     */
-    public function applyStyle(Cell $cell, Style $style)
-    {
-        $mergedStyle = $this->styleMerger->merge($cell->getStyle(), $style);
-        $cell->setStyle($mergedStyle);
-    }
-}
diff --git a/lib/openspout/src/Writer/Common/Manager/ManagesCellSize.php b/lib/openspout/src/Writer/Common/Manager/ManagesCellSize.php
deleted file mode 100644
index eb8c4a4f0ba..00000000000
--- a/lib/openspout/src/Writer/Common/Manager/ManagesCellSize.php
+++ /dev/null
@@ -1,62 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\Common\Manager;
-
-trait ManagesCellSize
-{
-    /** @var null|float The default column width to use */
-    private $defaultColumnWidth;
-
-    /** @var null|float The default row height to use */
-    private $defaultRowHeight;
-
-    /** @var array Array of min-max-width arrays */
-    private $columnWidths = [];
-
-    /**
-     * @param null|float $width
-     */
-    public function setDefaultColumnWidth($width)
-    {
-        $this->defaultColumnWidth = $width;
-    }
-
-    /**
-     * @param null|float $height
-     */
-    public function setDefaultRowHeight($height)
-    {
-        $this->defaultRowHeight = $height;
-    }
-
-    /**
-     * @param int ...$columns One or more columns with this width
-     */
-    public function setColumnWidth(float $width, ...$columns)
-    {
-        // Gather sequences
-        $sequence = [];
-        foreach ($columns as $i) {
-            $sequenceLength = \count($sequence);
-            if ($sequenceLength > 0) {
-                $previousValue = $sequence[$sequenceLength - 1];
-                if ($i !== $previousValue + 1) {
-                    $this->setColumnWidthForRange($width, $sequence[0], $previousValue);
-                    $sequence = [];
-                }
-            }
-            $sequence[] = $i;
-        }
-        $this->setColumnWidthForRange($width, $sequence[0], $sequence[\count($sequence) - 1]);
-    }
-
-    /**
-     * @param float $width The width to set
-     * @param int   $start First column index of the range
-     * @param int   $end   Last column index of the range
-     */
-    public function setColumnWidthForRange(float $width, int $start, int $end)
-    {
-        $this->columnWidths[] = [$start, $end, $width];
-    }
-}
diff --git a/lib/openspout/src/Writer/Common/Manager/RegisteredStyle.php b/lib/openspout/src/Writer/Common/Manager/RegisteredStyle.php
index d3ef877ae8d..1144cee528b 100644
--- a/lib/openspout/src/Writer/Common/Manager/RegisteredStyle.php
+++ b/lib/openspout/src/Writer/Common/Manager/RegisteredStyle.php
@@ -1,23 +1,21 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Manager;
 
 use OpenSpout\Common\Entity\Style\Style;
 
 /**
  * Allow to know if this style must replace actual row style.
+ *
+ * @internal
  */
-class RegisteredStyle
+final class RegisteredStyle
 {
-    /**
-     * @var Style
-     */
-    private $style;
+    private Style $style;
 
-    /**
-     * @var bool
-     */
-    private $isMatchingRowStyle;
+    private bool $isMatchingRowStyle;
 
     public function __construct(Style $style, bool $isMatchingRowStyle)
     {
diff --git a/lib/openspout/src/Writer/Common/Manager/RowManager.php b/lib/openspout/src/Writer/Common/Manager/RowManager.php
deleted file mode 100644
index e702bf7af61..00000000000
--- a/lib/openspout/src/Writer/Common/Manager/RowManager.php
+++ /dev/null
@@ -1,25 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\Common\Manager;
-
-use OpenSpout\Common\Entity\Row;
-
-class RowManager
-{
-    /**
-     * Detect whether a row is considered empty.
-     * An empty row has all of its cells empty.
-     *
-     * @return bool
-     */
-    public function isEmpty(Row $row)
-    {
-        foreach ($row->getCells() as $cell) {
-            if (!$cell->isEmpty()) {
-                return false;
-            }
-        }
-
-        return true;
-    }
-}
diff --git a/lib/openspout/src/Writer/Common/Manager/SheetManager.php b/lib/openspout/src/Writer/Common/Manager/SheetManager.php
index 4d6a6c236c1..937093f4cb1 100644
--- a/lib/openspout/src/Writer/Common/Manager/SheetManager.php
+++ b/lib/openspout/src/Writer/Common/Manager/SheetManager.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Manager;
 
 use OpenSpout\Common\Helper\StringHelper;
@@ -7,21 +9,24 @@ use OpenSpout\Writer\Common\Entity\Sheet;
 use OpenSpout\Writer\Exception\InvalidSheetNameException;
 
 /**
- * Sheet manager.
+ * @internal
  */
-class SheetManager
+final class SheetManager
 {
-    /** Sheet name should not exceed 31 characters */
+    /**
+     * Sheet name should not exceed 31 characters.
+     */
     public const MAX_LENGTH_SHEET_NAME = 31;
 
-    /** @var array Invalid characters that cannot be contained in the sheet name */
-    private static $INVALID_CHARACTERS_IN_SHEET_NAME = ['\\', '/', '?', '*', ':', '[', ']'];
+    /**
+     * Invalid characters that cannot be contained in the sheet name.
+     */
+    private const INVALID_CHARACTERS_IN_SHEET_NAME = ['\\', '/', '?', '*', ':', '[', ']'];
 
-    /** @var array Associative array [WORKBOOK_ID] => [[SHEET_INDEX] => [SHEET_NAME]] keeping track of sheets' name to enforce uniqueness per workbook */
-    private static $SHEETS_NAME_USED = [];
+    /** @var array<string, array<int, string>> Associative array [WORKBOOK_ID] => [[SHEET_INDEX] => [SHEET_NAME]] keeping track of sheets' name to enforce uniqueness per workbook */
+    private static array $SHEETS_NAME_USED = [];
 
-    /** @var StringHelper */
-    private $stringHelper;
+    private StringHelper $stringHelper;
 
     /**
      * SheetManager constructor.
@@ -36,40 +41,30 @@ class SheetManager
      *
      * @see Sheet::setName for validity rules.
      *
-     * @param string $name
-     * @param Sheet  $sheet The sheet whose future name is checked
+     * @param Sheet $sheet The sheet whose future name is checked
      *
      * @throws \OpenSpout\Writer\Exception\InvalidSheetNameException if the sheet's name is invalid
      */
-    public function throwIfNameIsInvalid($name, Sheet $sheet)
+    public function throwIfNameIsInvalid(string $name, Sheet $sheet): void
     {
-        if (!\is_string($name)) {
-            $actualType = \gettype($name);
-            $errorMessage = "The sheet's name is invalid. It must be a string ({$actualType} given).";
-
-            throw new InvalidSheetNameException($errorMessage);
-        }
-
         $failedRequirements = [];
         $nameLength = $this->stringHelper->getStringLength($name);
 
         if (!$this->isNameUnique($name, $sheet)) {
             $failedRequirements[] = 'It should be unique';
+        } elseif (0 === $nameLength) {
+            $failedRequirements[] = 'It should not be blank';
         } else {
-            if (0 === $nameLength) {
-                $failedRequirements[] = 'It should not be blank';
-            } else {
-                if ($nameLength > self::MAX_LENGTH_SHEET_NAME) {
-                    $failedRequirements[] = 'It should not exceed 31 characters';
-                }
+            if ($nameLength > self::MAX_LENGTH_SHEET_NAME) {
+                $failedRequirements[] = 'It should not exceed 31 characters';
+            }
 
-                if ($this->doesContainInvalidCharacters($name)) {
-                    $failedRequirements[] = 'It should not contain these characters: \\ / ? * : [ or ]';
-                }
+            if ($this->doesContainInvalidCharacters($name)) {
+                $failedRequirements[] = 'It should not contain these characters: \\ / ? * : [ or ]';
+            }
 
-                if ($this->doesStartOrEndWithSingleQuote($name)) {
-                    $failedRequirements[] = 'It should not start or end with a single quote';
-                }
+            if ($this->doesStartOrEndWithSingleQuote($name)) {
+                $failedRequirements[] = 'It should not start or end with a single quote';
             }
         }
 
@@ -84,14 +79,14 @@ class SheetManager
     /**
      * @param string $workbookId Workbook ID associated to a Sheet
      */
-    public function markWorkbookIdAsUsed($workbookId)
+    public function markWorkbookIdAsUsed(string $workbookId): void
     {
         if (!isset(self::$SHEETS_NAME_USED[$workbookId])) {
             self::$SHEETS_NAME_USED[$workbookId] = [];
         }
     }
 
-    public function markSheetNameAsUsed(Sheet $sheet)
+    public function markSheetNameAsUsed(Sheet $sheet): void
     {
         self::$SHEETS_NAME_USED[$sheet->getAssociatedWorkbookId()][$sheet->getIndex()] = $sheet->getName();
     }
@@ -99,25 +94,19 @@ class SheetManager
     /**
      * Returns whether the given name contains at least one invalid character.
      *
-     * @see Sheet::$INVALID_CHARACTERS_IN_SHEET_NAME for the full list.
-     *
-     * @param string $name
-     *
      * @return bool TRUE if the name contains invalid characters, FALSE otherwise
      */
-    private function doesContainInvalidCharacters($name)
+    private function doesContainInvalidCharacters(string $name): bool
     {
-        return str_replace(self::$INVALID_CHARACTERS_IN_SHEET_NAME, '', $name) !== $name;
+        return str_replace(self::INVALID_CHARACTERS_IN_SHEET_NAME, '', $name) !== $name;
     }
 
     /**
      * Returns whether the given name starts or ends with a single quote.
      *
-     * @param string $name
-     *
      * @return bool TRUE if the name starts or ends with a single quote, FALSE otherwise
      */
-    private function doesStartOrEndWithSingleQuote($name)
+    private function doesStartOrEndWithSingleQuote(string $name): bool
     {
         $startsWithSingleQuote = (0 === $this->stringHelper->getCharFirstOccurrencePosition('\'', $name));
         $endsWithSingleQuote = ($this->stringHelper->getCharLastOccurrencePosition('\'', $name) === ($this->stringHelper->getStringLength($name) - 1));
@@ -128,12 +117,11 @@ class SheetManager
     /**
      * Returns whether the given name is unique.
      *
-     * @param string $name
-     * @param Sheet  $sheet The sheet whose future name is checked
+     * @param Sheet $sheet The sheet whose future name is checked
      *
      * @return bool TRUE if the name is unique, FALSE otherwise
      */
-    private function isNameUnique($name, Sheet $sheet)
+    private function isNameUnique(string $name, Sheet $sheet): bool
     {
         foreach (self::$SHEETS_NAME_USED[$sheet->getAssociatedWorkbookId()] as $sheetIndex => $sheetName) {
             if ($sheetIndex !== $sheet->getIndex() && $sheetName === $name) {
diff --git a/lib/openspout/src/Writer/Common/Manager/Style/StyleManager.php b/lib/openspout/src/Writer/Common/Manager/Style/AbstractStyleManager.php
similarity index 73%
rename from lib/openspout/src/Writer/Common/Manager/Style/StyleManager.php
rename to lib/openspout/src/Writer/Common/Manager/Style/AbstractStyleManager.php
index 47f4d34cf3f..f9c1624c793 100644
--- a/lib/openspout/src/Writer/Common/Manager/Style/StyleManager.php
+++ b/lib/openspout/src/Writer/Common/Manager/Style/AbstractStyleManager.php
@@ -1,19 +1,21 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Manager\Style;
 
 use OpenSpout\Common\Entity\Cell;
 use OpenSpout\Common\Entity\Style\Style;
 
 /**
- * Manages styles to be applied to a cell.
+ * @internal
  */
-class StyleManager implements StyleManagerInterface
+abstract class AbstractStyleManager implements StyleManagerInterface
 {
-    /** @var StyleRegistry Registry for all used styles */
-    protected $styleRegistry;
+    /** @var AbstractStyleRegistry Registry for all used styles */
+    protected AbstractStyleRegistry $styleRegistry;
 
-    public function __construct(StyleRegistry $styleRegistry)
+    public function __construct(AbstractStyleRegistry $styleRegistry)
     {
         $this->styleRegistry = $styleRegistry;
     }
@@ -26,7 +28,7 @@ class StyleManager implements StyleManagerInterface
      *
      * @return Style the registered style, updated with an internal ID
      */
-    public function registerStyle($style)
+    final public function registerStyle(Style $style): Style
     {
         return $this->styleRegistry->registerStyle($style);
     }
@@ -37,7 +39,7 @@ class StyleManager implements StyleManagerInterface
      *
      * @return PossiblyUpdatedStyle The eventually updated style
      */
-    public function applyExtraStylesIfNeeded(Cell $cell): PossiblyUpdatedStyle
+    final public function applyExtraStylesIfNeeded(Cell $cell): PossiblyUpdatedStyle
     {
         return $this->applyWrapTextIfCellContainsNewLine($cell);
     }
@@ -47,7 +49,7 @@ class StyleManager implements StyleManagerInterface
      *
      * @return Style Default style
      */
-    protected function getDefaultStyle()
+    final protected function getDefaultStyle(): Style
     {
         // By construction, the default style has ID 0
         return $this->styleRegistry->getRegisteredStyles()[0];
@@ -66,12 +68,12 @@ class StyleManager implements StyleManagerInterface
      *
      * @return PossiblyUpdatedStyle The eventually updated style
      */
-    protected function applyWrapTextIfCellContainsNewLine(Cell $cell): PossiblyUpdatedStyle
+    private function applyWrapTextIfCellContainsNewLine(Cell $cell): PossiblyUpdatedStyle
     {
         $cellStyle = $cell->getStyle();
 
         // if the "wrap text" option is already set, no-op
-        if (!$cellStyle->hasSetWrapText() && $cell->isString() && false !== strpos($cell->getValue(), "\n")) {
+        if (!$cellStyle->hasSetWrapText() && $cell instanceof Cell\StringCell && str_contains($cell->getValue(), "\n")) {
             $cellStyle->setShouldWrapText();
 
             return new PossiblyUpdatedStyle($cellStyle, true);
diff --git a/lib/openspout/src/Writer/Common/Manager/Style/StyleRegistry.php b/lib/openspout/src/Writer/Common/Manager/Style/AbstractStyleRegistry.php
similarity index 66%
rename from lib/openspout/src/Writer/Common/Manager/Style/StyleRegistry.php
rename to lib/openspout/src/Writer/Common/Manager/Style/AbstractStyleRegistry.php
index b3782a02cc1..433c6f544df 100644
--- a/lib/openspout/src/Writer/Common/Manager/Style/StyleRegistry.php
+++ b/lib/openspout/src/Writer/Common/Manager/Style/AbstractStyleRegistry.php
@@ -1,19 +1,21 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Manager\Style;
 
 use OpenSpout\Common\Entity\Style\Style;
 
 /**
- * Registry for all used styles.
+ * @internal
  */
-class StyleRegistry
+abstract class AbstractStyleRegistry
 {
-    /** @var array [SERIALIZED_STYLE] => [STYLE_ID] mapping table, keeping track of the registered styles */
-    protected $serializedStyleToStyleIdMappingTable = [];
+    /** @var array<string, int> [SERIALIZED_STYLE] => [STYLE_ID] mapping table, keeping track of the registered styles */
+    private array $serializedStyleToStyleIdMappingTable = [];
 
-    /** @var array [STYLE_ID] => [STYLE] mapping table, keeping track of the registered styles */
-    protected $styleIdToStyleMappingTable = [];
+    /** @var array<int, Style> [STYLE_ID] => [STYLE] mapping table, keeping track of the registered styles */
+    private array $styleIdToStyleMappingTable = [];
 
     public function __construct(Style $defaultStyle)
     {
@@ -29,7 +31,7 @@ class StyleRegistry
      *
      * @return Style the registered style, updated with an internal ID
      */
-    public function registerStyle(Style $style)
+    public function registerStyle(Style $style): Style
     {
         $serializedStyle = $this->serialize($style);
 
@@ -47,17 +49,12 @@ class StyleRegistry
     /**
      * @return Style[] List of registered styles
      */
-    public function getRegisteredStyles()
+    final public function getRegisteredStyles(): array
     {
         return array_values($this->styleIdToStyleMappingTable);
     }
 
-    /**
-     * @param int $styleId
-     *
-     * @return Style
-     */
-    public function getStyleFromStyleId($styleId)
+    final public function getStyleFromStyleId(int $styleId): Style
     {
         return $this->styleIdToStyleMappingTable[$styleId];
     }
@@ -69,27 +66,17 @@ class StyleRegistry
      *
      * @return string The serialized style
      */
-    public function serialize(Style $style)
+    final public function serialize(Style $style): string
     {
-        // In order to be able to properly compare style, set static ID value and reset registration
-        $currentId = $style->getId();
-        $style->unmarkAsRegistered();
-
-        $serializedStyle = serialize($style);
-
-        $style->markAsRegistered($currentId);
-
-        return $serializedStyle;
+        return serialize($style);
     }
 
     /**
      * Returns whether the serialized style has already been registered.
      *
      * @param string $serializedStyle The serialized style
-     *
-     * @return bool
      */
-    protected function hasSerializedStyleAlreadyBeenRegistered(string $serializedStyle)
+    private function hasSerializedStyleAlreadyBeenRegistered(string $serializedStyle): bool
     {
         // Using isset here because it is way faster than array_key_exists...
         return isset($this->serializedStyleToStyleIdMappingTable[$serializedStyle]);
@@ -99,10 +86,8 @@ class StyleRegistry
      * Returns the registered style associated to the given serialization.
      *
      * @param string $serializedStyle The serialized style from which the actual style should be fetched from
-     *
-     * @return Style
      */
-    protected function getStyleFromSerializedStyle($serializedStyle)
+    private function getStyleFromSerializedStyle(string $serializedStyle): Style
     {
         $styleId = $this->serializedStyleToStyleIdMappingTable[$serializedStyle];
 
diff --git a/lib/openspout/src/Writer/Common/Manager/Style/PossiblyUpdatedStyle.php b/lib/openspout/src/Writer/Common/Manager/Style/PossiblyUpdatedStyle.php
index d78dd4b0b0f..c147c35aa6d 100644
--- a/lib/openspout/src/Writer/Common/Manager/Style/PossiblyUpdatedStyle.php
+++ b/lib/openspout/src/Writer/Common/Manager/Style/PossiblyUpdatedStyle.php
@@ -1,17 +1,18 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Manager\Style;
 
 use OpenSpout\Common\Entity\Style\Style;
 
 /**
- * Indicates if style is updated.
- * It allow to know if style registration must be done.
+ * @internal
  */
-class PossiblyUpdatedStyle
+final class PossiblyUpdatedStyle
 {
-    private $style;
-    private $isUpdated;
+    private Style $style;
+    private bool $isUpdated;
 
     public function __construct(Style $style, bool $isUpdated)
     {
diff --git a/lib/openspout/src/Writer/Common/Manager/Style/StyleManagerInterface.php b/lib/openspout/src/Writer/Common/Manager/Style/StyleManagerInterface.php
index 0418f3dac33..a2f401d06c7 100644
--- a/lib/openspout/src/Writer/Common/Manager/Style/StyleManagerInterface.php
+++ b/lib/openspout/src/Writer/Common/Manager/Style/StyleManagerInterface.php
@@ -1,12 +1,14 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Manager\Style;
 
 use OpenSpout\Common\Entity\Cell;
 use OpenSpout\Common\Entity\Style\Style;
 
 /**
- * Interface StyleHManagernterface.
+ * @internal
  */
 interface StyleManagerInterface
 {
@@ -18,7 +20,7 @@ interface StyleManagerInterface
      *
      * @return Style the registered style, updated with an internal ID
      */
-    public function registerStyle($style);
+    public function registerStyle(Style $style): Style;
 
     /**
      * Apply additional styles if the given row needs it.
diff --git a/lib/openspout/src/Writer/Common/Manager/Style/StyleMerger.php b/lib/openspout/src/Writer/Common/Manager/Style/StyleMerger.php
index a1f18af60f4..eb9fe2444f2 100644
--- a/lib/openspout/src/Writer/Common/Manager/Style/StyleMerger.php
+++ b/lib/openspout/src/Writer/Common/Manager/Style/StyleMerger.php
@@ -1,13 +1,15 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Manager\Style;
 
 use OpenSpout\Common\Entity\Style\Style;
 
 /**
- * Takes care of merging styles together.
+ * @internal
  */
-class StyleMerger
+final class StyleMerger
 {
     /**
      * Merges the current style with the given style, using the given style as a base. This means that:
@@ -19,7 +21,7 @@ class StyleMerger
      *
      * @return Style New style corresponding to the merge of the 2 styles
      */
-    public function merge(Style $style, Style $baseStyle)
+    public function merge(Style $style, Style $baseStyle): Style
     {
         $mergedStyle = clone $style;
 
@@ -33,7 +35,7 @@ class StyleMerger
     /**
      * @param Style $styleToUpdate (passed as reference)
      */
-    private function mergeFontStyles(Style $styleToUpdate, Style $style, Style $baseStyle)
+    private function mergeFontStyles(Style $styleToUpdate, Style $style, Style $baseStyle): void
     {
         if (!$style->hasSetFontBold() && $baseStyle->isFontBold()) {
             $styleToUpdate->setFontBold();
@@ -52,7 +54,7 @@ class StyleMerger
     /**
      * @param Style $styleToUpdate Style to update (passed as reference)
      */
-    private function mergeOtherFontProperties(Style $styleToUpdate, Style $style, Style $baseStyle)
+    private function mergeOtherFontProperties(Style $styleToUpdate, Style $style, Style $baseStyle): void
     {
         if (!$style->hasSetFontSize() && Style::DEFAULT_FONT_SIZE !== $baseStyle->getFontSize()) {
             $styleToUpdate->setFontSize($baseStyle->getFontSize());
@@ -68,10 +70,10 @@ class StyleMerger
     /**
      * @param Style $styleToUpdate Style to update (passed as reference)
      */
-    private function mergeCellProperties(Style $styleToUpdate, Style $style, Style $baseStyle)
+    private function mergeCellProperties(Style $styleToUpdate, Style $style, Style $baseStyle): void
     {
-        if (!$style->hasSetWrapText() && $baseStyle->shouldWrapText()) {
-            $styleToUpdate->setShouldWrapText();
+        if (!$style->hasSetWrapText() && $baseStyle->hasSetWrapText()) {
+            $styleToUpdate->setShouldWrapText($baseStyle->shouldWrapText());
         }
         if (!$style->hasSetShrinkToFit() && $baseStyle->shouldShrinkToFit()) {
             $styleToUpdate->setShouldShrinkToFit();
@@ -79,14 +81,17 @@ class StyleMerger
         if (!$style->hasSetCellAlignment() && $baseStyle->shouldApplyCellAlignment()) {
             $styleToUpdate->setCellAlignment($baseStyle->getCellAlignment());
         }
-        if (null === $style->getBorder() && $baseStyle->shouldApplyBorder()) {
-            $styleToUpdate->setBorder($baseStyle->getBorder());
+        if (!$style->hasSetCellVerticalAlignment() && $baseStyle->shouldApplyCellVerticalAlignment()) {
+            $styleToUpdate->setCellVerticalAlignment($baseStyle->getCellVerticalAlignment());
         }
-        if (null === $style->getFormat() && $baseStyle->shouldApplyFormat()) {
-            $styleToUpdate->setFormat($baseStyle->getFormat());
+        if (null === $style->getBorder() && null !== ($border = $baseStyle->getBorder())) {
+            $styleToUpdate->setBorder($border);
         }
-        if (!$style->shouldApplyBackgroundColor() && $baseStyle->shouldApplyBackgroundColor()) {
-            $styleToUpdate->setBackgroundColor($baseStyle->getBackgroundColor());
+        if (null === $style->getFormat() && null !== ($format = $baseStyle->getFormat())) {
+            $styleToUpdate->setFormat($format);
+        }
+        if (null === $style->getBackgroundColor() && null !== ($bgColor = $baseStyle->getBackgroundColor())) {
+            $styleToUpdate->setBackgroundColor($bgColor);
         }
     }
 }
diff --git a/lib/openspout/src/Writer/Common/Manager/WorkbookManagerInterface.php b/lib/openspout/src/Writer/Common/Manager/WorkbookManagerInterface.php
index 209abc6dc88..13082835be3 100644
--- a/lib/openspout/src/Writer/Common/Manager/WorkbookManagerInterface.php
+++ b/lib/openspout/src/Writer/Common/Manager/WorkbookManagerInterface.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Manager;
 
 use OpenSpout\Common\Entity\Row;
@@ -11,58 +13,31 @@ use OpenSpout\Writer\Exception\SheetNotFoundException;
 use OpenSpout\Writer\Exception\WriterException;
 
 /**
- * Interface WorkbookManagerInterface
- * workbook manager interface, providing the generic interfaces to work with workbook.
+ * @internal
  */
 interface WorkbookManagerInterface
 {
-    /**
-     * @return null|Workbook
-     */
-    public function getWorkbook();
-
     /**
      * Creates a new sheet in the workbook and make it the current sheet.
      * The writing will resume where it stopped (i.e. data won't be truncated).
      *
-     * @throws IOException If unable to open the sheet for writing
-     *
      * @return Worksheet The created sheet
+     *
+     * @throws IOException If unable to open the sheet for writing
      */
-    public function addNewSheetAndMakeItCurrent();
+    public function addNewSheetAndMakeItCurrent(): Worksheet;
 
     /**
      * @return Worksheet[] All the workbook's sheets
      */
-    public function getWorksheets();
+    public function getWorksheets(): array;
 
     /**
      * Returns the current sheet.
      *
      * @return Worksheet The current sheet
      */
-    public function getCurrentWorksheet();
-
-    /**
-     * Starts the current sheet and opens its file pointer.
-     */
-    public function startCurrentSheet();
-
-    public function setDefaultColumnWidth(float $width);
-
-    public function setDefaultRowHeight(float $height);
-
-    /**
-     * @param int ...$columns One or more columns with this width
-     */
-    public function setColumnWidth(float $width, ...$columns);
-
-    /**
-     * @param float $width The width to set
-     * @param int   $start First column index of the range
-     * @param int   $end   Last column index of the range
-     */
-    public function setColumnWidthForRange(float $width, int $start, int $end);
+    public function getCurrentWorksheet(): Worksheet;
 
     /**
      * Sets the given sheet as the current one. New data will be written to this sheet.
@@ -72,7 +47,7 @@ interface WorkbookManagerInterface
      *
      * @throws SheetNotFoundException If the given sheet does not exist in the workbook
      */
-    public function setCurrentSheet(Sheet $sheet);
+    public function setCurrentSheet(Sheet $sheet): void;
 
     /**
      * Adds a row to the current sheet.
@@ -84,7 +59,7 @@ interface WorkbookManagerInterface
      * @throws IOException     If trying to create a new sheet and unable to open the sheet for writing
      * @throws WriterException If unable to write data
      */
-    public function addRowToCurrentWorksheet(Row $row);
+    public function addRowToCurrentWorksheet(Row $row): void;
 
     /**
      * Closes the workbook and all its associated sheets.
@@ -93,5 +68,5 @@ interface WorkbookManagerInterface
      *
      * @param resource $finalFilePointer Pointer to the spreadsheet that will be created
      */
-    public function close($finalFilePointer);
+    public function close($finalFilePointer): void;
 }
diff --git a/lib/openspout/src/Writer/Common/Manager/WorksheetManagerInterface.php b/lib/openspout/src/Writer/Common/Manager/WorksheetManagerInterface.php
index a10e670394e..3817cbc5a57 100644
--- a/lib/openspout/src/Writer/Common/Manager/WorksheetManagerInterface.php
+++ b/lib/openspout/src/Writer/Common/Manager/WorksheetManagerInterface.php
@@ -1,38 +1,17 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Common\Manager;
 
 use OpenSpout\Common\Entity\Row;
 use OpenSpout\Writer\Common\Entity\Worksheet;
 
 /**
- * Interface WorksheetManagerInterface
- * Inteface for worksheet managers, providing the generic interfaces to work with worksheets.
+ * @internal
  */
 interface WorksheetManagerInterface
 {
-    /**
-     * @param null|float $width
-     */
-    public function setDefaultColumnWidth($width);
-
-    /**
-     * @param null|float $height
-     */
-    public function setDefaultRowHeight($height);
-
-    /**
-     * @param int ...$columns One or more columns with this width
-     */
-    public function setColumnWidth(float $width, ...$columns);
-
-    /**
-     * @param float $width The width to set
-     * @param int   $start First column index of the range
-     * @param int   $end   Last column index of the range
-     */
-    public function setColumnWidthForRange(float $width, int $start, int $end);
-
     /**
      * Adds a row to the worksheet.
      *
@@ -42,7 +21,7 @@ interface WorksheetManagerInterface
      * @throws \OpenSpout\Common\Exception\IOException              If the data cannot be written
      * @throws \OpenSpout\Common\Exception\InvalidArgumentException If a cell value's type is not supported
      */
-    public function addRow(Worksheet $worksheet, Row $row);
+    public function addRow(Worksheet $worksheet, Row $row): void;
 
     /**
      * Prepares the worksheet to accept data.
@@ -51,10 +30,10 @@ interface WorksheetManagerInterface
      *
      * @throws \OpenSpout\Common\Exception\IOException If the sheet data file cannot be opened for writing
      */
-    public function startSheet(Worksheet $worksheet);
+    public function startSheet(Worksheet $worksheet): void;
 
     /**
      * Closes the worksheet.
      */
-    public function close(Worksheet $worksheet);
+    public function close(Worksheet $worksheet): void;
 }
diff --git a/lib/openspout/src/Writer/Exception/Border/InvalidNameException.php b/lib/openspout/src/Writer/Exception/Border/InvalidNameException.php
index 626d0eaaa70..67897ab7e3a 100644
--- a/lib/openspout/src/Writer/Exception/Border/InvalidNameException.php
+++ b/lib/openspout/src/Writer/Exception/Border/InvalidNameException.php
@@ -1,16 +1,18 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Exception\Border;
 
 use OpenSpout\Common\Entity\Style\BorderPart;
 use OpenSpout\Writer\Exception\WriterException;
 
-class InvalidNameException extends WriterException
+final class InvalidNameException extends WriterException
 {
-    public function __construct($name)
+    public function __construct(string $name)
     {
         $msg = '%s is not a valid name identifier for a border. Valid identifiers are: %s.';
 
-        parent::__construct(sprintf($msg, $name, implode(',', BorderPart::getAllowedNames())));
+        parent::__construct(sprintf($msg, $name, implode(',', BorderPart::allowedNames)));
     }
 }
diff --git a/lib/openspout/src/Writer/Exception/Border/InvalidStyleException.php b/lib/openspout/src/Writer/Exception/Border/InvalidStyleException.php
index 5a811a3088b..ab03b20a24e 100644
--- a/lib/openspout/src/Writer/Exception/Border/InvalidStyleException.php
+++ b/lib/openspout/src/Writer/Exception/Border/InvalidStyleException.php
@@ -1,16 +1,18 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Exception\Border;
 
 use OpenSpout\Common\Entity\Style\BorderPart;
 use OpenSpout\Writer\Exception\WriterException;
 
-class InvalidStyleException extends WriterException
+final class InvalidStyleException extends WriterException
 {
-    public function __construct($name)
+    public function __construct(string $name)
     {
         $msg = '%s is not a valid style identifier for a border. Valid identifiers are: %s.';
 
-        parent::__construct(sprintf($msg, $name, implode(',', BorderPart::getAllowedStyles())));
+        parent::__construct(sprintf($msg, $name, implode(',', BorderPart::allowedStyles)));
     }
 }
diff --git a/lib/openspout/src/Writer/Exception/Border/InvalidWidthException.php b/lib/openspout/src/Writer/Exception/Border/InvalidWidthException.php
index 5c43261c7f0..43d4021b0a6 100644
--- a/lib/openspout/src/Writer/Exception/Border/InvalidWidthException.php
+++ b/lib/openspout/src/Writer/Exception/Border/InvalidWidthException.php
@@ -1,16 +1,18 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Exception\Border;
 
 use OpenSpout\Common\Entity\Style\BorderPart;
 use OpenSpout\Writer\Exception\WriterException;
 
-class InvalidWidthException extends WriterException
+final class InvalidWidthException extends WriterException
 {
-    public function __construct($name)
+    public function __construct(string $name)
     {
         $msg = '%s is not a valid width identifier for a border. Valid identifiers are: %s.';
 
-        parent::__construct(sprintf($msg, $name, implode(',', BorderPart::getAllowedWidths())));
+        parent::__construct(sprintf($msg, $name, implode(',', BorderPart::allowedWidths)));
     }
 }
diff --git a/lib/openspout/src/Writer/Exception/InvalidSheetNameException.php b/lib/openspout/src/Writer/Exception/InvalidSheetNameException.php
index 62e3a716a62..a01add1ebdf 100644
--- a/lib/openspout/src/Writer/Exception/InvalidSheetNameException.php
+++ b/lib/openspout/src/Writer/Exception/InvalidSheetNameException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Exception;
 
-class InvalidSheetNameException extends WriterException
+final class InvalidSheetNameException extends WriterException
 {
 }
diff --git a/lib/openspout/src/Writer/Exception/SheetNotFoundException.php b/lib/openspout/src/Writer/Exception/SheetNotFoundException.php
index 3c249519d79..25622c13835 100644
--- a/lib/openspout/src/Writer/Exception/SheetNotFoundException.php
+++ b/lib/openspout/src/Writer/Exception/SheetNotFoundException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Exception;
 
-class SheetNotFoundException extends WriterException
+final class SheetNotFoundException extends WriterException
 {
 }
diff --git a/lib/openspout/src/Writer/Exception/WriterAlreadyOpenedException.php b/lib/openspout/src/Writer/Exception/WriterAlreadyOpenedException.php
index 4d45999881f..b91b3e8f471 100644
--- a/lib/openspout/src/Writer/Exception/WriterAlreadyOpenedException.php
+++ b/lib/openspout/src/Writer/Exception/WriterAlreadyOpenedException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Exception;
 
-class WriterAlreadyOpenedException extends WriterException
+final class WriterAlreadyOpenedException extends WriterException
 {
 }
diff --git a/lib/openspout/src/Writer/Exception/WriterException.php b/lib/openspout/src/Writer/Exception/WriterException.php
index b3d927f082f..270cbb712e9 100644
--- a/lib/openspout/src/Writer/Exception/WriterException.php
+++ b/lib/openspout/src/Writer/Exception/WriterException.php
@@ -1,9 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Exception;
 
-use OpenSpout\Common\Exception\SpoutException;
+use OpenSpout\Common\Exception\OpenSpoutException;
 
-abstract class WriterException extends SpoutException
+abstract class WriterException extends OpenSpoutException
 {
 }
diff --git a/lib/openspout/src/Writer/Exception/WriterNotOpenedException.php b/lib/openspout/src/Writer/Exception/WriterNotOpenedException.php
index 1ec2d0d21a5..39b06fd3999 100644
--- a/lib/openspout/src/Writer/Exception/WriterNotOpenedException.php
+++ b/lib/openspout/src/Writer/Exception/WriterNotOpenedException.php
@@ -1,7 +1,9 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\Exception;
 
-class WriterNotOpenedException extends WriterException
+final class WriterNotOpenedException extends WriterException
 {
 }
diff --git a/lib/openspout/src/Writer/ODS/Creator/HelperFactory.php b/lib/openspout/src/Writer/ODS/Creator/HelperFactory.php
deleted file mode 100644
index d0c0c420ab5..00000000000
--- a/lib/openspout/src/Writer/ODS/Creator/HelperFactory.php
+++ /dev/null
@@ -1,54 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\ODS\Creator;
-
-use OpenSpout\Common\Helper\Escaper;
-use OpenSpout\Common\Helper\StringHelper;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Writer\Common\Creator\InternalEntityFactory;
-use OpenSpout\Writer\Common\Entity\Options;
-use OpenSpout\Writer\Common\Helper\ZipHelper;
-use OpenSpout\Writer\ODS\Helper\FileSystemHelper;
-
-/**
- * Factory for helpers needed by the ODS Writer.
- */
-class HelperFactory extends \OpenSpout\Common\Creator\HelperFactory
-{
-    /**
-     * @return FileSystemHelper
-     */
-    public function createSpecificFileSystemHelper(OptionsManagerInterface $optionsManager, InternalEntityFactory $entityFactory)
-    {
-        $tempFolder = $optionsManager->getOption(Options::TEMP_FOLDER);
-        $zipHelper = $this->createZipHelper($entityFactory);
-
-        return new FileSystemHelper($tempFolder, $zipHelper);
-    }
-
-    /**
-     * @return Escaper\ODS
-     */
-    public function createStringsEscaper()
-    {
-        return new Escaper\ODS();
-    }
-
-    /**
-     * @return StringHelper
-     */
-    public function createStringHelper()
-    {
-        return new StringHelper();
-    }
-
-    /**
-     * @param InternalEntityFactory $entityFactory
-     *
-     * @return ZipHelper
-     */
-    private function createZipHelper($entityFactory)
-    {
-        return new ZipHelper($entityFactory);
-    }
-}
diff --git a/lib/openspout/src/Writer/ODS/Creator/ManagerFactory.php b/lib/openspout/src/Writer/ODS/Creator/ManagerFactory.php
deleted file mode 100644
index a514286de54..00000000000
--- a/lib/openspout/src/Writer/ODS/Creator/ManagerFactory.php
+++ /dev/null
@@ -1,107 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\ODS\Creator;
-
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Writer\Common\Creator\InternalEntityFactory;
-use OpenSpout\Writer\Common\Creator\ManagerFactoryInterface;
-use OpenSpout\Writer\Common\Entity\Options;
-use OpenSpout\Writer\Common\Manager\SheetManager;
-use OpenSpout\Writer\Common\Manager\Style\StyleMerger;
-use OpenSpout\Writer\ODS\Manager\Style\StyleManager;
-use OpenSpout\Writer\ODS\Manager\Style\StyleRegistry;
-use OpenSpout\Writer\ODS\Manager\WorkbookManager;
-use OpenSpout\Writer\ODS\Manager\WorksheetManager;
-
-/**
- * Factory for managers needed by the ODS Writer.
- */
-class ManagerFactory implements ManagerFactoryInterface
-{
-    /** @var InternalEntityFactory */
-    protected $entityFactory;
-
-    /** @var HelperFactory */
-    protected $helperFactory;
-
-    public function __construct(InternalEntityFactory $entityFactory, HelperFactory $helperFactory)
-    {
-        $this->entityFactory = $entityFactory;
-        $this->helperFactory = $helperFactory;
-    }
-
-    /**
-     * @return WorkbookManager
-     */
-    public function createWorkbookManager(OptionsManagerInterface $optionsManager)
-    {
-        $workbook = $this->entityFactory->createWorkbook();
-
-        $fileSystemHelper = $this->helperFactory->createSpecificFileSystemHelper($optionsManager, $this->entityFactory);
-        $fileSystemHelper->createBaseFilesAndFolders();
-
-        $styleMerger = $this->createStyleMerger();
-        $styleManager = $this->createStyleManager($optionsManager);
-        $worksheetManager = $this->createWorksheetManager($styleManager, $styleMerger);
-
-        return new WorkbookManager(
-            $workbook,
-            $optionsManager,
-            $worksheetManager,
-            $styleManager,
-            $styleMerger,
-            $fileSystemHelper,
-            $this->entityFactory,
-            $this
-        );
-    }
-
-    /**
-     * @return SheetManager
-     */
-    public function createSheetManager()
-    {
-        $stringHelper = $this->helperFactory->createStringHelper();
-
-        return new SheetManager($stringHelper);
-    }
-
-    /**
-     * @return WorksheetManager
-     */
-    private function createWorksheetManager(StyleManager $styleManager, StyleMerger $styleMerger)
-    {
-        $stringsEscaper = $this->helperFactory->createStringsEscaper();
-        $stringsHelper = $this->helperFactory->createStringHelper();
-
-        return new WorksheetManager($styleManager, $styleMerger, $stringsEscaper, $stringsHelper);
-    }
-
-    /**
-     * @return StyleManager
-     */
-    private function createStyleManager(OptionsManagerInterface $optionsManager)
-    {
-        $styleRegistry = $this->createStyleRegistry($optionsManager);
-
-        return new StyleManager($styleRegistry, $optionsManager);
-    }
-
-    /**
-     * @return StyleRegistry
-     */
-    private function createStyleRegistry(OptionsManagerInterface $optionsManager)
-    {
-        $defaultRowStyle = $optionsManager->getOption(Options::DEFAULT_ROW_STYLE);
-
-        return new StyleRegistry($defaultRowStyle);
-    }
-
-    /**
-     * @return StyleMerger
-     */
-    private function createStyleMerger()
-    {
-        return new StyleMerger();
-    }
-}
diff --git a/lib/openspout/src/Writer/ODS/Helper/BorderHelper.php b/lib/openspout/src/Writer/ODS/Helper/BorderHelper.php
index caaf9544e22..f043f762079 100644
--- a/lib/openspout/src/Writer/ODS/Helper/BorderHelper.php
+++ b/lib/openspout/src/Writer/ODS/Helper/BorderHelper.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\ODS\Helper;
 
 use OpenSpout\Common\Entity\Style\Border;
@@ -16,15 +18,15 @@ use OpenSpout\Common\Entity\Style\BorderPart;
  * fo:border-bottom="0.74pt solid #ffc000" style:diagonal-bl-tr="none"
  * style:diagonal-tl-br="none" fo:border-left="none" fo:border-right="none"
  * style:rotation-align="none" fo:border-top="none"/>
+ *
+ * @internal
  */
-class BorderHelper
+final class BorderHelper
 {
     /**
      * Width mappings.
-     *
-     * @var array
      */
-    protected static $widthMap = [
+    public const widthMap = [
         Border::WIDTH_THIN => '0.75pt',
         Border::WIDTH_MEDIUM => '1.75pt',
         Border::WIDTH_THICK => '2.5pt',
@@ -32,20 +34,15 @@ class BorderHelper
 
     /**
      * Style mapping.
-     *
-     * @var array
      */
-    protected static $styleMap = [
+    public const styleMap = [
         Border::STYLE_SOLID => 'solid',
         Border::STYLE_DASHED => 'dashed',
         Border::STYLE_DOTTED => 'dotted',
         Border::STYLE_DOUBLE => 'double',
     ];
 
-    /**
-     * @return string
-     */
-    public static function serializeBorderPart(BorderPart $borderPart)
+    public static function serializeBorderPart(BorderPart $borderPart): string
     {
         $definition = 'fo:border-%s="%s"';
 
@@ -53,8 +50,8 @@ class BorderHelper
             $borderPartDefinition = sprintf($definition, $borderPart->getName(), 'none');
         } else {
             $attributes = [
-                self::$widthMap[$borderPart->getWidth()],
-                self::$styleMap[$borderPart->getStyle()],
+                self::widthMap[$borderPart->getWidth()],
+                self::styleMap[$borderPart->getStyle()],
                 '#'.$borderPart->getColor(),
             ];
             $borderPartDefinition = sprintf($definition, $borderPart->getName(), implode(' ', $attributes));
diff --git a/lib/openspout/src/Writer/ODS/Helper/FileSystemHelper.php b/lib/openspout/src/Writer/ODS/Helper/FileSystemHelper.php
index b3280b6a303..12f07ac4658 100644
--- a/lib/openspout/src/Writer/ODS/Helper/FileSystemHelper.php
+++ b/lib/openspout/src/Writer/ODS/Helper/FileSystemHelper.php
@@ -1,7 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\ODS\Helper;
 
+use DateTimeImmutable;
+use OpenSpout\Common\Helper\FileSystemHelper as CommonFileSystemHelper;
 use OpenSpout\Writer\Common\Entity\Worksheet;
 use OpenSpout\Writer\Common\Helper\FileSystemWithRootFolderHelperInterface;
 use OpenSpout\Writer\Common\Helper\ZipHelper;
@@ -9,16 +13,14 @@ use OpenSpout\Writer\ODS\Manager\Style\StyleManager;
 use OpenSpout\Writer\ODS\Manager\WorksheetManager;
 
 /**
- * This class provides helper functions to help with the file system operations
- * like files/folders creation & deletion for ODS files.
+ * @internal
  */
-class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper implements FileSystemWithRootFolderHelperInterface
+final class FileSystemHelper implements FileSystemWithRootFolderHelperInterface
 {
-    public const APP_NAME = 'Spout';
+    public const APP_NAME = 'OpenSpout';
     public const MIMETYPE = 'application/vnd.oasis.opendocument.spreadsheet';
 
     public const META_INF_FOLDER_NAME = 'META-INF';
-    public const SHEETS_CONTENT_TEMP_FOLDER_NAME = 'worksheets-temp';
 
     public const MANIFEST_XML_FILE_NAME = 'manifest.xml';
     public const CONTENT_XML_FILE_NAME = 'content.xml';
@@ -26,40 +28,58 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
     public const MIMETYPE_FILE_NAME = 'mimetype';
     public const STYLES_XML_FILE_NAME = 'styles.xml';
 
+    private string $baseFolderRealPath;
+    private CommonFileSystemHelper $baseFileSystemHelper;
+
     /** @var string Path to the root folder inside the temp folder where the files to create the ODS will be stored */
-    protected $rootFolder;
+    private string $rootFolder;
 
     /** @var string Path to the "META-INF" folder inside the root folder */
-    protected $metaInfFolder;
+    private string $metaInfFolder;
 
     /** @var string Path to the temp folder, inside the root folder, where specific sheets content will be written to */
-    protected $sheetsContentTempFolder;
+    private string $sheetsContentTempFolder;
 
     /** @var ZipHelper Helper to perform tasks with Zip archive */
-    private $zipHelper;
+    private ZipHelper $zipHelper;
 
     /**
      * @param string    $baseFolderPath The path of the base folder where all the I/O can occur
      * @param ZipHelper $zipHelper      Helper to perform tasks with Zip archive
      */
-    public function __construct($baseFolderPath, $zipHelper)
+    public function __construct(string $baseFolderPath, ZipHelper $zipHelper)
     {
-        parent::__construct($baseFolderPath);
+        $this->baseFileSystemHelper = new CommonFileSystemHelper($baseFolderPath);
+        $this->baseFolderRealPath = $this->baseFileSystemHelper->getBaseFolderRealPath();
         $this->zipHelper = $zipHelper;
     }
 
-    /**
-     * @return string
-     */
-    public function getRootFolder()
+    public function createFolder(string $parentFolderPath, string $folderName): string
+    {
+        return $this->baseFileSystemHelper->createFolder($parentFolderPath, $folderName);
+    }
+
+    public function createFileWithContents(string $parentFolderPath, string $fileName, string $fileContents): string
+    {
+        return $this->baseFileSystemHelper->createFileWithContents($parentFolderPath, $fileName, $fileContents);
+    }
+
+    public function deleteFile(string $filePath): void
+    {
+        $this->baseFileSystemHelper->deleteFile($filePath);
+    }
+
+    public function deleteFolderRecursively(string $folderPath): void
+    {
+        $this->baseFileSystemHelper->deleteFolderRecursively($folderPath);
+    }
+
+    public function getRootFolder(): string
     {
         return $this->rootFolder;
     }
 
-    /**
-     * @return string
-     */
-    public function getSheetsContentTempFolder()
+    public function getSheetsContentTempFolder(): string
     {
         return $this->sheetsContentTempFolder;
     }
@@ -69,7 +89,7 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create at least one of the base folders
      */
-    public function createBaseFilesAndFolders()
+    public function createBaseFilesAndFolders(): void
     {
         $this
             ->createRootFolder()
@@ -83,13 +103,9 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
     /**
      * Creates the "content.xml" file under the root folder.
      *
-     * @param WorksheetManager $worksheetManager
-     * @param StyleManager     $styleManager
-     * @param Worksheet[]      $worksheets
-     *
-     * @return FileSystemHelper
+     * @param Worksheet[] $worksheets
      */
-    public function createContentFile($worksheetManager, $styleManager, $worksheets)
+    public function createContentFile(WorksheetManager $worksheetManager, StyleManager $styleManager, array $worksheets): self
     {
         $contentXmlFileContents = <<<'EOD'
             <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
@@ -101,11 +117,20 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
 
         $contentXmlFileContents .= '<office:body><office:spreadsheet>';
 
-        $this->createFileWithContents($this->rootFolder, self::CONTENT_XML_FILE_NAME, $contentXmlFileContents);
+        $topContentTempFile = uniqid(self::CONTENT_XML_FILE_NAME);
+        $this->createFileWithContents($this->rootFolder, $topContentTempFile, $contentXmlFileContents);
 
         // Append sheets content to "content.xml"
-        $contentXmlFilePath = $this->rootFolder.'/'.self::CONTENT_XML_FILE_NAME;
-        $contentXmlHandle = fopen($contentXmlFilePath, 'a');
+        $contentXmlFilePath = $this->rootFolder.\DIRECTORY_SEPARATOR.self::CONTENT_XML_FILE_NAME;
+        $contentXmlHandle = fopen($contentXmlFilePath, 'w');
+        \assert(false !== $contentXmlHandle);
+
+        $topContentTempPathname = $this->rootFolder.\DIRECTORY_SEPARATOR.$topContentTempFile;
+        $topContentTempHandle = fopen($topContentTempPathname, 'r');
+        \assert(false !== $topContentTempHandle);
+        stream_copy_to_stream($topContentTempHandle, $contentXmlHandle);
+        fclose($topContentTempHandle);
+        unlink($topContentTempPathname);
 
         foreach ($worksheets as $worksheet) {
             // write the "<table:table>" node, with the final sheet's name
@@ -117,6 +142,17 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
             fwrite($contentXmlHandle, '</table:table>');
         }
 
+        // add AutoFilter
+        $databaseRanges = '';
+        foreach ($worksheets as $worksheet) {
+            $databaseRanges .= $worksheetManager->getTableDatabaseRangeElementAsString($worksheet);
+        }
+        if ('' !== $databaseRanges) {
+            fwrite($contentXmlHandle, '<table:database-ranges>');
+            fwrite($contentXmlHandle, $databaseRanges);
+            fwrite($contentXmlHandle, '</table:database-ranges>');
+        }
+
         $contentXmlFileContents = '</office:spreadsheet></office:body></office:document-content>';
 
         fwrite($contentXmlHandle, $contentXmlFileContents);
@@ -127,10 +163,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
 
     /**
      * Deletes the temporary folder where sheets content was stored.
-     *
-     * @return FileSystemHelper
      */
-    public function deleteWorksheetTempFolder()
+    public function deleteWorksheetTempFolder(): self
     {
         $this->deleteFolderRecursively($this->sheetsContentTempFolder);
 
@@ -140,12 +174,9 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
     /**
      * Creates the "styles.xml" file under the root folder.
      *
-     * @param StyleManager $styleManager
-     * @param int          $numWorksheets Number of created worksheets
-     *
-     * @return FileSystemHelper
+     * @param int $numWorksheets Number of created worksheets
      */
-    public function createStylesFile($styleManager, $numWorksheets)
+    public function createStylesFile(StyleManager $styleManager, int $numWorksheets): self
     {
         $stylesXmlFileContents = $styleManager->getStylesXMLFileContent($numWorksheets);
         $this->createFileWithContents($this->rootFolder, self::STYLES_XML_FILE_NAME, $stylesXmlFileContents);
@@ -158,7 +189,7 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      *
      * @param resource $streamPointer Pointer to the stream to copy the zip
      */
-    public function zipRootFolderAndCopyToStream($streamPointer)
+    public function zipRootFolderAndCopyToStream($streamPointer): void
     {
         $zip = $this->zipHelper->createZip($this->rootFolder);
 
@@ -180,10 +211,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the folder that will be used as root.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder
-     *
-     * @return FileSystemHelper
      */
-    protected function createRootFolder()
+    private function createRootFolder(): self
     {
         $this->rootFolder = $this->createFolder($this->baseFolderRealPath, uniqid('ods'));
 
@@ -194,10 +223,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "META-INF" folder under the root folder as well as the "manifest.xml" file in it.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder or the "manifest.xml" file
-     *
-     * @return FileSystemHelper
      */
-    protected function createMetaInfoFolderAndFile()
+    private function createMetaInfoFolderAndFile(): self
     {
         $this->metaInfFolder = $this->createFolder($this->rootFolder, self::META_INF_FOLDER_NAME);
 
@@ -210,10 +237,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "manifest.xml" file under the "META-INF" folder (under root).
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the file
-     *
-     * @return FileSystemHelper
      */
-    protected function createManifestFile()
+    private function createManifestFile(): self
     {
         $manifestXmlFileContents = <<<'EOD'
             <?xml version="1.0" encoding="UTF-8"?>
@@ -235,12 +260,10 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * This folder is not part of the final ODS file and is only used to be able to jump between sheets.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder
-     *
-     * @return FileSystemHelper
      */
-    protected function createSheetsContentTempFolder()
+    private function createSheetsContentTempFolder(): self
     {
-        $this->sheetsContentTempFolder = $this->createFolder($this->rootFolder, self::SHEETS_CONTENT_TEMP_FOLDER_NAME);
+        $this->sheetsContentTempFolder = $this->createFolder($this->rootFolder, 'worksheets-temp');
 
         return $this;
     }
@@ -249,13 +272,11 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "meta.xml" file under the root folder.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the file
-     *
-     * @return FileSystemHelper
      */
-    protected function createMetaFile()
+    private function createMetaFile(): self
     {
         $appName = self::APP_NAME;
-        $createdDate = (new \DateTime())->format(\DateTime::W3C);
+        $createdDate = (new DateTimeImmutable())->format(DateTimeImmutable::W3C);
 
         $metaXmlFileContents = <<<EOD
             <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
@@ -277,10 +298,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "mimetype" file under the root folder.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the file
-     *
-     * @return FileSystemHelper
      */
-    protected function createMimetypeFile()
+    private function createMimetypeFile(): self
     {
         $this->createFileWithContents($this->rootFolder, self::MIMETYPE_FILE_NAME, self::MIMETYPE);
 
@@ -295,9 +314,10 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * @param string   $sourceFilePath Path of the file whose content will be copied
      * @param resource $targetResource Target resource that will receive the content
      */
-    protected function copyFileContentsToTarget($sourceFilePath, $targetResource)
+    private function copyFileContentsToTarget(string $sourceFilePath, $targetResource): void
     {
         $sourceHandle = fopen($sourceFilePath, 'r');
+        \assert(false !== $sourceHandle);
         stream_copy_to_stream($sourceHandle, $targetResource);
         fclose($sourceHandle);
     }
diff --git a/lib/openspout/src/Writer/ODS/Manager/OptionsManager.php b/lib/openspout/src/Writer/ODS/Manager/OptionsManager.php
deleted file mode 100644
index d098abf96b1..00000000000
--- a/lib/openspout/src/Writer/ODS/Manager/OptionsManager.php
+++ /dev/null
@@ -1,50 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\ODS\Manager;
-
-use OpenSpout\Common\Manager\OptionsManagerAbstract;
-use OpenSpout\Writer\Common\Creator\Style\StyleBuilder;
-use OpenSpout\Writer\Common\Entity\Options;
-
-/**
- * ODS Writer options manager.
- */
-class OptionsManager extends OptionsManagerAbstract
-{
-    /** @var StyleBuilder Style builder */
-    protected $styleBuilder;
-
-    /**
-     * OptionsManager constructor.
-     */
-    public function __construct(StyleBuilder $styleBuilder)
-    {
-        $this->styleBuilder = $styleBuilder;
-        parent::__construct();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function getSupportedOptions()
-    {
-        return [
-            Options::TEMP_FOLDER,
-            Options::DEFAULT_ROW_STYLE,
-            Options::SHOULD_CREATE_NEW_SHEETS_AUTOMATICALLY,
-            Options::DEFAULT_COLUMN_WIDTH,
-            Options::DEFAULT_ROW_HEIGHT,
-            Options::COLUMN_WIDTHS,
-        ];
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function setDefaultOptions()
-    {
-        $this->setOption(Options::TEMP_FOLDER, sys_get_temp_dir());
-        $this->setOption(Options::DEFAULT_ROW_STYLE, $this->styleBuilder->build());
-        $this->setOption(Options::SHOULD_CREATE_NEW_SHEETS_AUTOMATICALLY, true);
-    }
-}
diff --git a/lib/openspout/src/Writer/ODS/Manager/Style/StyleManager.php b/lib/openspout/src/Writer/ODS/Manager/Style/StyleManager.php
index e1d99764b6f..967d33dea72 100644
--- a/lib/openspout/src/Writer/ODS/Manager/Style/StyleManager.php
+++ b/lib/openspout/src/Writer/ODS/Manager/Style/StyleManager.php
@@ -1,41 +1,41 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\ODS\Manager\Style;
 
+use OpenSpout\Common\Entity\Style\Border;
 use OpenSpout\Common\Entity\Style\BorderPart;
 use OpenSpout\Common\Entity\Style\CellAlignment;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Writer\Common\Entity\Options;
+use OpenSpout\Common\Entity\Style\CellVerticalAlignment;
+use OpenSpout\Common\Entity\Style\Style;
+use OpenSpout\Writer\Common\AbstractOptions;
+use OpenSpout\Writer\Common\ColumnWidth;
 use OpenSpout\Writer\Common\Entity\Worksheet;
-use OpenSpout\Writer\Common\Manager\ManagesCellSize;
+use OpenSpout\Writer\Common\Manager\Style\AbstractStyleManager as CommonStyleManager;
 use OpenSpout\Writer\ODS\Helper\BorderHelper;
 
 /**
- * Manages styles to be applied to a cell.
+ * @internal
+ *
+ * @property StyleRegistry $styleRegistry
  */
-class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
+final class StyleManager extends CommonStyleManager
 {
-    use ManagesCellSize;
+    private AbstractOptions $options;
 
-    /** @var StyleRegistry */
-    protected $styleRegistry;
-
-    public function __construct(StyleRegistry $styleRegistry, OptionsManagerInterface $optionsManager)
+    public function __construct(StyleRegistry $styleRegistry, AbstractOptions $options)
     {
         parent::__construct($styleRegistry);
-        $this->setDefaultColumnWidth($optionsManager->getOption(Options::DEFAULT_COLUMN_WIDTH));
-        $this->setDefaultRowHeight($optionsManager->getOption(Options::DEFAULT_ROW_HEIGHT));
-        $this->columnWidths = $optionsManager->getOption(Options::COLUMN_WIDTHS) ?? [];
+        $this->options = $options;
     }
 
     /**
      * Returns the content of the "styles.xml" file, given a list of styles.
      *
      * @param int $numWorksheets Number of worksheets created
-     *
-     * @return string
      */
-    public function getStylesXMLFileContent($numWorksheets)
+    public function getStylesXMLFileContent(int $numWorksheets): string
     {
         $content = <<<'EOD'
             <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
@@ -56,10 +56,8 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the contents of the "<office:font-face-decls>" section, inside "content.xml" file.
-     *
-     * @return string
      */
-    public function getContentXmlFontFaceSectionContent()
+    public function getContentXmlFontFaceSectionContent(): string
     {
         $content = '<office:font-face-decls>';
         foreach ($this->styleRegistry->getUsedFonts() as $fontName) {
@@ -74,10 +72,8 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
      * Returns the contents of the "<office:automatic-styles>" section, inside "content.xml" file.
      *
      * @param Worksheet[] $worksheets
-     *
-     * @return string
      */
-    public function getContentXmlAutomaticStylesSectionContent($worksheets)
+    public function getContentXmlAutomaticStylesSectionContent(array $worksheets): string
     {
         $content = '<office:automatic-styles>';
 
@@ -85,9 +81,9 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
             $content .= $this->getStyleSectionContent($style);
         }
 
-        $useOptimalRowHeight = empty($this->defaultRowHeight) ? 'true' : 'false';
-        $defaultRowHeight = empty($this->defaultRowHeight) ? '15pt' : "{$this->defaultRowHeight}pt";
-        $defaultColumnWidth = empty($this->defaultColumnWidth) ? '' : "style:column-width=\"{$this->defaultColumnWidth}pt\"";
+        $useOptimalRowHeight = null === $this->options->DEFAULT_ROW_HEIGHT ? 'true' : 'false';
+        $defaultRowHeight = null === $this->options->DEFAULT_ROW_HEIGHT ? '15pt' : "{$this->options->DEFAULT_ROW_HEIGHT}pt";
+        $defaultColumnWidth = null === $this->options->DEFAULT_COLUMN_WIDTH ? '' : "style:column-width=\"{$this->options->DEFAULT_COLUMN_WIDTH}pt\"";
 
         $content .= <<<EOD
             <style:style style:family="table-column" style:name="default-column-style">
@@ -110,12 +106,9 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
         }
 
         // Sort column widths since ODS cares about order
-        usort($this->columnWidths, function ($a, $b) {
-            if ($a[0] === $b[0]) {
-                return 0;
-            }
-
-            return ($a[0] < $b[0]) ? -1 : 1;
+        $columnWidths = $this->options->getColumnWidths();
+        usort($columnWidths, static function (ColumnWidth $a, ColumnWidth $b): int {
+            return $a->start <=> $b->start;
         });
         $content .= $this->getTableColumnStylesXMLContent();
 
@@ -126,15 +119,15 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     public function getTableColumnStylesXMLContent(): string
     {
-        if (empty($this->columnWidths)) {
+        if ([] === $this->options->getColumnWidths()) {
             return '';
         }
 
         $content = '';
-        foreach ($this->columnWidths as $styleIndex => $entry) {
+        foreach ($this->options->getColumnWidths() as $styleIndex => $columnWidth) {
             $content .= <<<EOD
                 <style:style style:family="table-column" style:name="co{$styleIndex}">
-                    <style:table-column-properties fo:break-before="auto" style:use-optimal-column-width="false" style:column-width="{$entry[2]}pt"/>
+                    <style:table-column-properties fo:break-before="auto" style:use-optimal-column-width="false" style:column-width="{$columnWidth->width}pt"/>
                 </style:style>
                 EOD;
         }
@@ -144,46 +137,29 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     public function getStyledTableColumnXMLContent(int $maxNumColumns): string
     {
-        if (empty($this->columnWidths)) {
+        if ([] === $this->options->getColumnWidths()) {
             return '';
         }
 
         $content = '';
-        foreach ($this->columnWidths as $styleIndex => $entry) {
-            $numCols = $entry[1] - $entry[0] + 1;
+        foreach ($this->options->getColumnWidths() as $styleIndex => $columnWidth) {
+            $numCols = $columnWidth->end - $columnWidth->start + 1;
             $content .= <<<EOD
                 <table:table-column table:default-cell-style-name='Default' table:style-name="co{$styleIndex}" table:number-columns-repeated="{$numCols}"/>
                 EOD;
         }
+        \assert(isset($columnWidth));
         // Note: This assumes the column widths are contiguous and default width is
         // only applied to columns after the last custom column with a custom width
-        $content .= '<table:table-column table:default-cell-style-name="ce1" table:style-name="default-column-style" table:number-columns-repeated="'.($maxNumColumns - $entry[1]).'"/>';
-
-        return $content;
-    }
-
-    /**
-     * Returns the content of the "<office:font-face-decls>" section, inside "styles.xml" file.
-     *
-     * @return string
-     */
-    protected function getFontFaceSectionContent()
-    {
-        $content = '<office:font-face-decls>';
-        foreach ($this->styleRegistry->getUsedFonts() as $fontName) {
-            $content .= '<style:font-face style:name="'.$fontName.'" svg:font-family="'.$fontName.'"/>';
-        }
-        $content .= '</office:font-face-decls>';
+        $content .= '<table:table-column table:default-cell-style-name="ce1" table:style-name="default-column-style" table:number-columns-repeated="'.($maxNumColumns - $columnWidth->end).'"/>';
 
         return $content;
     }
 
     /**
      * Returns the content of the "<office:styles>" section, inside "styles.xml" file.
-     *
-     * @return string
      */
-    protected function getStylesSectionContent()
+    private function getStylesSectionContent(): string
     {
         $defaultStyle = $this->getDefaultStyle();
 
@@ -202,40 +178,12 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
             EOD;
     }
 
-    /**
-     * Returns the content of the "<office:automatic-styles>" section, inside "styles.xml" file.
-     *
-     * @param int $numWorksheets Number of worksheets created
-     *
-     * @return string
-     */
-    protected function getAutomaticStylesSectionContent($numWorksheets)
-    {
-        $content = '<office:automatic-styles>';
-
-        for ($i = 1; $i <= $numWorksheets; ++$i) {
-            $content .= <<<EOD
-                <style:page-layout style:name="pm{$i}">
-                    <style:page-layout-properties style:first-page-number="continue" style:print="objects charts drawings" style:table-centering="none"/>
-                    <style:header-style/>
-                    <style:footer-style/>
-                </style:page-layout>
-                EOD;
-        }
-
-        $content .= '</office:automatic-styles>';
-
-        return $content;
-    }
-
     /**
      * Returns the content of the "<office:master-styles>" section, inside "styles.xml" file.
      *
      * @param int $numWorksheets Number of worksheets created
-     *
-     * @return string
      */
-    protected function getMasterStylesSectionContent($numWorksheets)
+    private function getMasterStylesSectionContent(int $numWorksheets): string
     {
         $content = '<office:master-styles>';
 
@@ -256,13 +204,47 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
     }
 
     /**
-     * Returns the contents of the "<style:style>" section, inside "<office:automatic-styles>" section.
-     *
-     * @param \OpenSpout\Common\Entity\Style\Style $style
-     *
-     * @return string
+     * Returns the content of the "<office:font-face-decls>" section, inside "styles.xml" file.
      */
-    protected function getStyleSectionContent($style)
+    private function getFontFaceSectionContent(): string
+    {
+        $content = '<office:font-face-decls>';
+        foreach ($this->styleRegistry->getUsedFonts() as $fontName) {
+            $content .= '<style:font-face style:name="'.$fontName.'" svg:font-family="'.$fontName.'"/>';
+        }
+        $content .= '</office:font-face-decls>';
+
+        return $content;
+    }
+
+    /**
+     * Returns the content of the "<office:automatic-styles>" section, inside "styles.xml" file.
+     *
+     * @param int $numWorksheets Number of worksheets created
+     */
+    private function getAutomaticStylesSectionContent(int $numWorksheets): string
+    {
+        $content = '<office:automatic-styles>';
+
+        for ($i = 1; $i <= $numWorksheets; ++$i) {
+            $content .= <<<EOD
+                <style:page-layout style:name="pm{$i}">
+                    <style:page-layout-properties style:first-page-number="continue" style:print="objects charts drawings" style:table-centering="none"/>
+                    <style:header-style/>
+                    <style:footer-style/>
+                </style:page-layout>
+                EOD;
+        }
+
+        $content .= '</office:automatic-styles>';
+
+        return $content;
+    }
+
+    /**
+     * Returns the contents of the "<style:style>" section, inside "<office:automatic-styles>" section.
+     */
+    private function getStyleSectionContent(Style $style): string
     {
         $styleIndex = $style->getId() + 1; // 1-based
 
@@ -279,12 +261,8 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the contents of the "<style:text-properties>" section, inside "<style:style>" section.
-     *
-     * @param \OpenSpout\Common\Entity\Style\Style $style
-     *
-     * @return string
      */
-    private function getTextPropertiesSectionContent($style)
+    private function getTextPropertiesSectionContent(Style $style): string
     {
         if (!$style->shouldApplyFont()) {
             return '';
@@ -297,12 +275,8 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the contents of the fonts definition section, inside "<style:text-properties>" section.
-     *
-     * @param \OpenSpout\Common\Entity\Style\Style $style
-     *
-     * @return string
      */
-    private function getFontSectionContent($style)
+    private function getFontSectionContent(Style $style): string
     {
         $defaultStyle = $this->getDefaultStyle();
         $content = '';
@@ -340,81 +314,91 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the contents of the "<style:paragraph-properties>" section, inside "<style:style>" section.
-     *
-     * @param \OpenSpout\Common\Entity\Style\Style $style
-     *
-     * @return string
      */
-    private function getParagraphPropertiesSectionContent($style)
+    private function getParagraphPropertiesSectionContent(Style $style): string
     {
-        if (!$style->shouldApplyCellAlignment()) {
+        if (!$style->shouldApplyCellAlignment() && !$style->shouldApplyCellVerticalAlignment()) {
             return '';
         }
 
         return '<style:paragraph-properties '
             .$this->getCellAlignmentSectionContent($style)
+            .$this->getCellVerticalAlignmentSectionContent($style)
             .'/>';
     }
 
     /**
      * Returns the contents of the cell alignment definition for the "<style:paragraph-properties>" section.
-     *
-     * @param \OpenSpout\Common\Entity\Style\Style $style
-     *
-     * @return string
      */
-    private function getCellAlignmentSectionContent($style)
+    private function getCellAlignmentSectionContent(Style $style): string
     {
+        if (!$style->hasSetCellAlignment()) {
+            return '';
+        }
+
         return sprintf(
             ' fo:text-align="%s" ',
             $this->transformCellAlignment($style->getCellAlignment())
         );
     }
 
+    /**
+     * Returns the contents of the cell vertical alignment definition for the "<style:paragraph-properties>" section.
+     */
+    private function getCellVerticalAlignmentSectionContent(Style $style): string
+    {
+        if (!$style->hasSetCellVerticalAlignment()) {
+            return '';
+        }
+
+        return sprintf(
+            ' fo:vertical-align="%s" ',
+            $this->transformCellVerticalAlignment($style->getCellVerticalAlignment())
+        );
+    }
+
     /**
      * Even though "left" and "right" alignments are part of the spec, and interpreted
      * respectively as "start" and "end", using the recommended values increase compatibility
      * with software that will read the created ODS file.
-     *
-     * @param string $cellAlignment
-     *
-     * @return string
      */
-    private function transformCellAlignment($cellAlignment)
+    private function transformCellAlignment(string $cellAlignment): string
     {
-        switch ($cellAlignment) {
-            case CellAlignment::LEFT:
-                return 'start';
+        return match ($cellAlignment) {
+            CellAlignment::LEFT => 'start',
+            CellAlignment::RIGHT => 'end',
+            default => $cellAlignment,
+        };
+    }
 
-            case CellAlignment::RIGHT:
-                return 'end';
-
-            default:
-                return $cellAlignment;
-        }
+    /**
+     * Spec uses 'middle' rather than 'center'
+     * http://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os-part1.html#__RefHeading__1420236_253892949.
+     */
+    private function transformCellVerticalAlignment(string $cellVerticalAlignment): string
+    {
+        return (CellVerticalAlignment::CENTER === $cellVerticalAlignment)
+            ? 'middle'
+            : $cellVerticalAlignment;
     }
 
     /**
      * Returns the contents of the "<style:table-cell-properties>" section, inside "<style:style>" section.
-     *
-     * @param \OpenSpout\Common\Entity\Style\Style $style
-     *
-     * @return string
      */
-    private function getTableCellPropertiesSectionContent($style)
+    private function getTableCellPropertiesSectionContent(Style $style): string
     {
         $content = '<style:table-cell-properties ';
 
-        if ($style->shouldWrapText()) {
-            $content .= $this->getWrapTextXMLContent();
+        if ($style->hasSetWrapText()) {
+            $content .= $this->getWrapTextXMLContent($style->shouldWrapText());
         }
 
-        if ($style->shouldApplyBorder()) {
-            $content .= $this->getBorderXMLContent($style);
+        if (null !== ($border = $style->getBorder())) {
+            $content .= $this->getBorderXMLContent($border);
         }
 
-        if ($style->shouldApplyBackgroundColor()) {
-            $content .= $this->getBackgroundColorXMLContent($style);
+        if (null !== ($bgColor = $style->getBackgroundColor())) {
+            $content .= $this->getBackgroundColorXMLContent($bgColor);
         }
 
         $content .= '/>';
@@ -424,39 +408,29 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the contents of the wrap text definition for the "<style:table-cell-properties>" section.
-     *
-     * @return string
      */
-    private function getWrapTextXMLContent()
+    private function getWrapTextXMLContent(bool $shouldWrapText): string
     {
-        return ' fo:wrap-option="wrap" style:vertical-align="automatic" ';
+        return ' fo:wrap-option="'.($shouldWrapText ? '' : 'no-').'wrap" style:vertical-align="automatic" ';
     }
 
     /**
      * Returns the contents of the borders definition for the "<style:table-cell-properties>" section.
-     *
-     * @param \OpenSpout\Common\Entity\Style\Style $style
-     *
-     * @return string
      */
-    private function getBorderXMLContent($style)
+    private function getBorderXMLContent(Border $border): string
     {
-        $borders = array_map(function (BorderPart $borderPart) {
+        $borders = array_map(static function (BorderPart $borderPart) {
             return BorderHelper::serializeBorderPart($borderPart);
-        }, $style->getBorder()->getParts());
+        }, $border->getParts());
 
         return sprintf(' %s ', implode(' ', $borders));
     }
 
     /**
      * Returns the contents of the background color definition for the "<style:table-cell-properties>" section.
-     *
-     * @param \OpenSpout\Common\Entity\Style\Style $style
-     *
-     * @return string
      */
-    private function getBackgroundColorXMLContent($style)
+    private function getBackgroundColorXMLContent(string $bgColor): string
     {
-        return sprintf(' fo:background-color="#%s" ', $style->getBackgroundColor());
+        return sprintf(' fo:background-color="#%s" ', $bgColor);
     }
 }
diff --git a/lib/openspout/src/Writer/ODS/Manager/Style/StyleRegistry.php b/lib/openspout/src/Writer/ODS/Manager/Style/StyleRegistry.php
index e90dc96b986..cdba6088c29 100644
--- a/lib/openspout/src/Writer/ODS/Manager/Style/StyleRegistry.php
+++ b/lib/openspout/src/Writer/ODS/Manager/Style/StyleRegistry.php
@@ -1,16 +1,19 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\ODS\Manager\Style;
 
 use OpenSpout\Common\Entity\Style\Style;
+use OpenSpout\Writer\Common\Manager\Style\AbstractStyleRegistry as CommonStyleRegistry;
 
 /**
- * Registry for all used styles.
+ * @internal
  */
-class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
+final class StyleRegistry extends CommonStyleRegistry
 {
-    /** @var array [FONT_NAME] => [] Map whose keys contain all the fonts used */
-    protected $usedFontsSet = [];
+    /** @var array<string, bool> [FONT_NAME] => [] Map whose keys contain all the fonts used */
+    private array $usedFontsSet = [];
 
     /**
      * Registers the given style as a used style.
@@ -20,7 +23,7 @@ class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
      *
      * @return Style the registered style, updated with an internal ID
      */
-    public function registerStyle(Style $style)
+    public function registerStyle(Style $style): Style
     {
         if ($style->isRegistered()) {
             return $style;
@@ -35,7 +38,7 @@ class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
     /**
      * @return string[] List of used fonts name
      */
-    public function getUsedFonts()
+    public function getUsedFonts(): array
     {
         return array_keys($this->usedFontsSet);
     }
diff --git a/lib/openspout/src/Writer/ODS/Manager/WorkbookManager.php b/lib/openspout/src/Writer/ODS/Manager/WorkbookManager.php
index 90dc0e4ace7..0da68f458f0 100644
--- a/lib/openspout/src/Writer/ODS/Manager/WorkbookManager.php
+++ b/lib/openspout/src/Writer/ODS/Manager/WorkbookManager.php
@@ -1,47 +1,55 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\ODS\Manager;
 
 use OpenSpout\Writer\Common\Entity\Sheet;
-use OpenSpout\Writer\Common\Manager\WorkbookManagerAbstract;
+use OpenSpout\Writer\Common\Entity\Workbook;
+use OpenSpout\Writer\Common\Manager\AbstractWorkbookManager;
+use OpenSpout\Writer\Common\Manager\Style\StyleMerger;
 use OpenSpout\Writer\ODS\Helper\FileSystemHelper;
 use OpenSpout\Writer\ODS\Manager\Style\StyleManager;
+use OpenSpout\Writer\ODS\Options;
 
 /**
- * ODS workbook manager, providing the interfaces to work with workbook.
+ * @internal
+ *
+ * @property WorksheetManager $worksheetManager
+ * @property FileSystemHelper $fileSystemHelper
+ * @property StyleManager     $styleManager
  */
-class WorkbookManager extends WorkbookManagerAbstract
+final class WorkbookManager extends AbstractWorkbookManager
 {
     /**
      * Maximum number of rows a ODS sheet can contain.
      *
      * @see https://ask.libreoffice.org/en/question/8631/upper-limit-to-number-of-rows-in-calc/
      */
-    protected static $maxRowsPerWorksheet = 1048576;
+    private static int $maxRowsPerWorksheet = 1048576;
 
-    /** @var WorksheetManager Object used to manage worksheets */
-    protected $worksheetManager;
-
-    /** @var FileSystemHelper Helper to perform file system operations */
-    protected $fileSystemHelper;
-
-    /** @var StyleManager Manages styles */
-    protected $styleManager;
-
-    /**
-     * @return string The file path where the data for the given sheet will be stored
-     */
-    public function getWorksheetFilePath(Sheet $sheet)
-    {
-        $sheetsContentTempFolder = $this->fileSystemHelper->getSheetsContentTempFolder();
-
-        return $sheetsContentTempFolder.'/sheet'.$sheet->getIndex().'.xml';
+    public function __construct(
+        Workbook $workbook,
+        Options $options,
+        WorksheetManager $worksheetManager,
+        StyleManager $styleManager,
+        StyleMerger $styleMerger,
+        FileSystemHelper $fileSystemHelper
+    ) {
+        parent::__construct(
+            $workbook,
+            $options,
+            $worksheetManager,
+            $styleManager,
+            $styleMerger,
+            $fileSystemHelper
+        );
     }
 
     /**
      * @return int Maximum number of rows/columns a sheet can contain
      */
-    protected function getMaxRowsPerWorksheet()
+    protected function getMaxRowsPerWorksheet(): int
     {
         return self::$maxRowsPerWorksheet;
     }
@@ -51,7 +59,7 @@ class WorkbookManager extends WorkbookManagerAbstract
      *
      * @param resource $finalFilePointer Pointer to the spreadsheet that will be created
      */
-    protected function writeAllFilesToDiskAndZipThem($finalFilePointer)
+    protected function writeAllFilesToDiskAndZipThem($finalFilePointer): void
     {
         $worksheets = $this->getWorksheets();
         $numWorksheets = \count($worksheets);
diff --git a/lib/openspout/src/Writer/ODS/Manager/WorksheetManager.php b/lib/openspout/src/Writer/ODS/Manager/WorksheetManager.php
index 3eeca5f2728..c77f72f43bf 100644
--- a/lib/openspout/src/Writer/ODS/Manager/WorksheetManager.php
+++ b/lib/openspout/src/Writer/ODS/Manager/WorksheetManager.php
@@ -1,36 +1,37 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\ODS\Manager;
 
+use DateTimeImmutable;
+use DateTimeInterface;
 use OpenSpout\Common\Entity\Cell;
 use OpenSpout\Common\Entity\Row;
 use OpenSpout\Common\Entity\Style\Style;
 use OpenSpout\Common\Exception\InvalidArgumentException;
 use OpenSpout\Common\Exception\IOException;
 use OpenSpout\Common\Helper\Escaper\ODS as ODSEscaper;
-use OpenSpout\Common\Helper\StringHelper;
 use OpenSpout\Writer\Common\Entity\Worksheet;
+use OpenSpout\Writer\Common\Helper\CellHelper;
 use OpenSpout\Writer\Common\Manager\RegisteredStyle;
 use OpenSpout\Writer\Common\Manager\Style\StyleMerger;
 use OpenSpout\Writer\Common\Manager\WorksheetManagerInterface;
 use OpenSpout\Writer\ODS\Manager\Style\StyleManager;
 
 /**
- * ODS worksheet manager, providing the interfaces to work with ODS worksheets.
+ * @internal
  */
-class WorksheetManager implements WorksheetManagerInterface
+final class WorksheetManager implements WorksheetManagerInterface
 {
-    /** @var \OpenSpout\Common\Helper\Escaper\ODS Strings escaper */
-    private $stringsEscaper;
-
-    /** @var StringHelper String helper */
-    private $stringHelper;
+    /** @var ODSEscaper Strings escaper */
+    private ODSEscaper $stringsEscaper;
 
     /** @var StyleManager Manages styles */
-    private $styleManager;
+    private StyleManager $styleManager;
 
     /** @var StyleMerger Helper to merge styles together */
-    private $styleMerger;
+    private StyleMerger $styleMerger;
 
     /**
      * WorksheetManager constructor.
@@ -38,13 +39,11 @@ class WorksheetManager implements WorksheetManagerInterface
     public function __construct(
         StyleManager $styleManager,
         StyleMerger $styleMerger,
-        ODSEscaper $stringsEscaper,
-        StringHelper $stringHelper
+        ODSEscaper $stringsEscaper
     ) {
         $this->styleManager = $styleManager;
         $this->styleMerger = $styleMerger;
         $this->stringsEscaper = $stringsEscaper;
-        $this->stringHelper = $stringHelper;
     }
 
     /**
@@ -54,10 +53,10 @@ class WorksheetManager implements WorksheetManagerInterface
      *
      * @throws \OpenSpout\Common\Exception\IOException If the sheet data file cannot be opened for writing
      */
-    public function startSheet(Worksheet $worksheet)
+    public function startSheet(Worksheet $worksheet): void
     {
         $sheetFilePointer = fopen($worksheet->getFilePath(), 'w');
-        $this->throwIfSheetFilePointerIsNotAvailable($sheetFilePointer);
+        \assert(false !== $sheetFilePointer);
 
         $worksheet->setFilePointer($sheetFilePointer);
     }
@@ -67,7 +66,7 @@ class WorksheetManager implements WorksheetManagerInterface
      *
      * @return string "<table>" node as string
      */
-    public function getTableElementStartAsString(Worksheet $worksheet)
+    public function getTableElementStartAsString(Worksheet $worksheet): string
     {
         $externalSheet = $worksheet->getExternalSheet();
         $escapedSheetName = $this->stringsEscaper->escape($externalSheet->getName());
@@ -79,6 +78,31 @@ class WorksheetManager implements WorksheetManagerInterface
         return $tableElement;
     }
 
+    /**
+     * Returns the table:database-range XML node for AutoFilter as string.
+     */
+    public function getTableDatabaseRangeElementAsString(Worksheet $worksheet): string
+    {
+        $externalSheet = $worksheet->getExternalSheet();
+        $escapedSheetName = $this->stringsEscaper->escape($externalSheet->getName());
+        $databaseRange = '';
+
+        if (null !== $autofilter = $externalSheet->getAutoFilter()) {
+            $rangeAddress = sprintf(
+                '\'%s\'.%s%s:\'%s\'.%s%s',
+                $escapedSheetName,
+                CellHelper::getColumnLettersFromColumnIndex($autofilter->fromColumnIndex),
+                $autofilter->fromRow,
+                $escapedSheetName,
+                CellHelper::getColumnLettersFromColumnIndex($autofilter->toColumnIndex),
+                $autofilter->toRow
+            );
+            $databaseRange = '<table:database-range table:name="__Anonymous_Sheet_DB__'.$externalSheet->getIndex().'" table:target-range-address="'.$rangeAddress.'" table:display-filter-buttons="true"/>';
+        }
+
+        return $databaseRange;
+    }
+
     /**
      * Adds a row to the given worksheet.
      *
@@ -88,7 +112,7 @@ class WorksheetManager implements WorksheetManagerInterface
      * @throws InvalidArgumentException If a cell value's type is not supported
      * @throws IOException              If the data cannot be written
      */
-    public function addRow(Worksheet $worksheet, Row $row)
+    public function addRow(Worksheet $worksheet, Row $row): void
     {
         $cells = $row->getCells();
         $rowStyle = $row->getStyle();
@@ -101,6 +125,7 @@ class WorksheetManager implements WorksheetManagerInterface
         for ($i = 0; $i < $row->getNumCells(); ++$i) {
             /** @var Cell $cell */
             $cell = $cells[$currentCellIndex];
+
             /** @var null|Cell $nextCell */
             $nextCell = $cells[$nextCellIndex] ?? null;
 
@@ -133,63 +158,9 @@ class WorksheetManager implements WorksheetManagerInterface
     /**
      * Closes the worksheet.
      */
-    public function close(Worksheet $worksheet)
+    public function close(Worksheet $worksheet): void
     {
-        $worksheetFilePointer = $worksheet->getFilePointer();
-
-        if (!\is_resource($worksheetFilePointer)) {
-            return;
-        }
-
-        fclose($worksheetFilePointer);
-    }
-
-    /**
-     * @param null|float $width
-     */
-    public function setDefaultColumnWidth($width)
-    {
-        $this->styleManager->setDefaultColumnWidth($width);
-    }
-
-    /**
-     * @param null|float $height
-     */
-    public function setDefaultRowHeight($height)
-    {
-        $this->styleManager->setDefaultRowHeight($height);
-    }
-
-    /**
-     * @param int ...$columns One or more columns with this width
-     */
-    public function setColumnWidth(float $width, ...$columns)
-    {
-        $this->styleManager->setColumnWidth($width, ...$columns);
-    }
-
-    /**
-     * @param float $width The width to set
-     * @param int   $start First column index of the range
-     * @param int   $end   Last column index of the range
-     */
-    public function setColumnWidthForRange(float $width, int $start, int $end)
-    {
-        $this->styleManager->setColumnWidthForRange($width, $start, $end);
-    }
-
-    /**
-     * Checks if the sheet has been sucessfully created. Throws an exception if not.
-     *
-     * @param bool|resource $sheetFilePointer Pointer to the sheet data file or FALSE if unable to open the file
-     *
-     * @throws IOException If the sheet data file cannot be opened for writing
-     */
-    private function throwIfSheetFilePointerIsNotAvailable($sheetFilePointer)
-    {
-        if (!$sheetFilePointer) {
-            throw new IOException('Unable to open sheet for writing.');
-        }
+        fclose($worksheet->getFilePointer());
     }
 
     /**
@@ -244,11 +215,11 @@ class WorksheetManager implements WorksheetManagerInterface
      * @param int  $styleIndex            Index of the used style
      * @param int  $numTimesValueRepeated Number of times the value is consecutively repeated
      *
-     * @throws InvalidArgumentException If a cell value's type is not supported
-     *
      * @return string The cell XML content
+     *
+     * @throws InvalidArgumentException If a cell value's type is not supported
      */
-    private function getCellXML(Cell $cell, $styleIndex, $numTimesValueRepeated)
+    private function getCellXML(Cell $cell, int $styleIndex, int $numTimesValueRepeated): string
     {
         $data = '<table:table-cell table:style-name="ce'.$styleIndex.'"';
 
@@ -256,7 +227,7 @@ class WorksheetManager implements WorksheetManagerInterface
             $data .= ' table:number-columns-repeated="'.$numTimesValueRepeated.'"';
         }
 
-        if ($cell->isString()) {
+        if ($cell instanceof Cell\StringCell) {
             $data .= ' office:value-type="string" calcext:value-type="string">';
 
             $cellValueLines = explode("\n", $cell->getValue());
@@ -265,42 +236,36 @@ class WorksheetManager implements WorksheetManagerInterface
             }
 
             $data .= '</table:table-cell>';
-        } elseif ($cell->isBoolean()) {
+        } elseif ($cell instanceof Cell\BooleanCell) {
             $value = $cell->getValue() ? 'true' : 'false'; // boolean-value spec: http://docs.oasis-open.org/office/v1.2/os/OpenDocument-v1.2-os-part1.html#datatype-boolean
             $data .= ' office:value-type="boolean" calcext:value-type="boolean" office:boolean-value="'.$value.'">';
             $data .= '<text:p>'.$cell->getValue().'</text:p>';
             $data .= '</table:table-cell>';
-        } elseif ($cell->isNumeric()) {
-            $cellValue = $this->stringHelper->formatNumericValue($cell->getValue());
+        } elseif ($cell instanceof Cell\NumericCell) {
+            $cellValue = $cell->getValue();
             $data .= ' office:value-type="float" calcext:value-type="float" office:value="'.$cellValue.'">';
             $data .= '<text:p>'.$cellValue.'</text:p>';
             $data .= '</table:table-cell>';
-        } elseif ($cell->isDate()) {
-            $value = $cell->getValue();
-            if ($value instanceof \DateTimeInterface) {
-                $datevalue = substr((new \DateTimeImmutable('@'.$value->getTimestamp()))->format(\DateTimeInterface::W3C), 0, -6);
-                $data .= ' office:value-type="date" calcext:value-type="date" office:date-value="'.$datevalue.'Z">';
-                $data .= '<text:p>'.$datevalue.'Z</text:p>';
-            } elseif ($value instanceof \DateInterval) {
-                // workaround for missing DateInterval::format('c'), see https://stackoverflow.com/a/61088115/53538
-                static $f = ['M0S', 'H0M', 'DT0H', 'M0D', 'Y0M', 'P0Y', 'Y0M', 'P0M'];
-                static $r = ['M', 'H', 'DT', 'M', 'Y0M', 'P', 'Y', 'P'];
-                $value = rtrim(str_replace($f, $r, $value->format('P%yY%mM%dDT%hH%iM%sS')), 'PT') ?: 'PT0S';
-                $data .= ' office:value-type="time" office:time-value="'.$value.'">';
-                $data .= '<text:p>'.$value.'</text:p>';
-            } else {
-                throw new InvalidArgumentException('Trying to add a date value with an unsupported type: '.\gettype($cell->getValue()));
-            }
+        } elseif ($cell instanceof Cell\DateTimeCell) {
+            $datevalue = substr((new DateTimeImmutable('@'.$cell->getValue()->getTimestamp()))->format(DateTimeInterface::W3C), 0, -6);
+            $data .= ' office:value-type="date" calcext:value-type="date" office:date-value="'.$datevalue.'Z">';
+            $data .= '<text:p>'.$datevalue.'Z</text:p>';
             $data .= '</table:table-cell>';
-        } elseif ($cell->isError() && \is_string($cell->getValueEvenIfError())) {
+        } elseif ($cell instanceof Cell\DateIntervalCell) {
+            // workaround for missing DateInterval::format('c'), see https://stackoverflow.com/a/61088115/53538
+            static $f = ['M0S', 'H0M', 'DT0H', 'M0D', 'Y0M', 'P0Y', 'Y0M', 'P0M'];
+            static $r = ['M', 'H', 'DT', 'M', 'Y0M', 'P', 'Y', 'P'];
+            $value = rtrim(str_replace($f, $r, $cell->getValue()->format('P%yY%mM%dDT%hH%iM%sS')), 'PT') ?: 'PT0S';
+            $data .= ' office:value-type="time" office:time-value="'.$value.'">';
+            $data .= '<text:p>'.$value.'</text:p>';
+            $data .= '</table:table-cell>';
+        } elseif ($cell instanceof Cell\ErrorCell) {
             // only writes the error value if it's a string
             $data .= ' office:value-type="string" calcext:value-type="error" office:value="">';
-            $data .= '<text:p>'.$cell->getValueEvenIfError().'</text:p>';
+            $data .= '<text:p>'.$cell->getRawValue().'</text:p>';
             $data .= '</table:table-cell>';
-        } elseif ($cell->isEmpty()) {
+        } elseif ($cell instanceof Cell\EmptyCell) {
             $data .= '/>';
-        } else {
-            throw new InvalidArgumentException('Trying to add a value with an unsupported type: '.\gettype($cell->getValue()));
         }
 
         return $data;
diff --git a/lib/openspout/src/Writer/ODS/Options.php b/lib/openspout/src/Writer/ODS/Options.php
new file mode 100644
index 00000000000..547ee2da805
--- /dev/null
+++ b/lib/openspout/src/Writer/ODS/Options.php
@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Writer\ODS;
+
+use OpenSpout\Writer\Common\AbstractOptions;
+
+final class Options extends AbstractOptions
+{
+}
diff --git a/lib/openspout/src/Writer/ODS/Writer.php b/lib/openspout/src/Writer/ODS/Writer.php
index 5f510e636e5..487fb6a30da 100644
--- a/lib/openspout/src/Writer/ODS/Writer.php
+++ b/lib/openspout/src/Writer/ODS/Writer.php
@@ -1,34 +1,54 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\ODS;
 
-use OpenSpout\Writer\Common\Entity\Options;
-use OpenSpout\Writer\WriterMultiSheetsAbstract;
+use OpenSpout\Common\Helper\Escaper\ODS;
+use OpenSpout\Writer\AbstractWriterMultiSheets;
+use OpenSpout\Writer\Common\Entity\Workbook;
+use OpenSpout\Writer\Common\Helper\ZipHelper;
+use OpenSpout\Writer\Common\Manager\Style\StyleMerger;
+use OpenSpout\Writer\ODS\Helper\FileSystemHelper;
+use OpenSpout\Writer\ODS\Manager\Style\StyleManager;
+use OpenSpout\Writer\ODS\Manager\Style\StyleRegistry;
+use OpenSpout\Writer\ODS\Manager\WorkbookManager;
+use OpenSpout\Writer\ODS\Manager\WorksheetManager;
 
-/**
- * This class provides base support to write data to ODS files.
- */
-class Writer extends WriterMultiSheetsAbstract
+final class Writer extends AbstractWriterMultiSheets
 {
     /** @var string Content-Type value for the header */
-    protected static $headerContentType = 'application/vnd.oasis.opendocument.spreadsheet';
+    protected static string $headerContentType = 'application/vnd.oasis.opendocument.spreadsheet';
+    private Options $options;
 
-    /**
-     * Sets a custom temporary folder for creating intermediate files/folders.
-     * This must be set before opening the writer.
-     *
-     * @param string $tempFolder Temporary folder where the files to create the ODS will be stored
-     *
-     * @throws \OpenSpout\Writer\Exception\WriterAlreadyOpenedException If the writer was already opened
-     *
-     * @return Writer
-     */
-    public function setTempFolder($tempFolder)
+    public function __construct(?Options $options = null)
     {
-        $this->throwIfWriterAlreadyOpened('Writer must be configured before opening it.');
+        $this->options = $options ?? new Options();
+    }
 
-        $this->optionsManager->setOption(Options::TEMP_FOLDER, $tempFolder);
+    public function getOptions(): Options
+    {
+        return $this->options;
+    }
 
-        return $this;
+    protected function createWorkbookManager(): WorkbookManager
+    {
+        $workbook = new Workbook();
+
+        $fileSystemHelper = new FileSystemHelper($this->options->getTempFolder(), new ZipHelper());
+        $fileSystemHelper->createBaseFilesAndFolders();
+
+        $styleMerger = new StyleMerger();
+        $styleManager = new StyleManager(new StyleRegistry($this->options->DEFAULT_ROW_STYLE), $this->options);
+        $worksheetManager = new WorksheetManager($styleManager, $styleMerger, new ODS());
+
+        return new WorkbookManager(
+            $workbook,
+            $this->options,
+            $worksheetManager,
+            $styleManager,
+            $styleMerger,
+            $fileSystemHelper
+        );
     }
 }
diff --git a/lib/openspout/src/Writer/WriterAbstract.php b/lib/openspout/src/Writer/WriterAbstract.php
deleted file mode 100644
index fd75617e2e0..00000000000
--- a/lib/openspout/src/Writer/WriterAbstract.php
+++ /dev/null
@@ -1,253 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer;
-
-use OpenSpout\Common\Creator\HelperFactory;
-use OpenSpout\Common\Entity\Row;
-use OpenSpout\Common\Entity\Style\Style;
-use OpenSpout\Common\Exception\InvalidArgumentException;
-use OpenSpout\Common\Exception\IOException;
-use OpenSpout\Common\Exception\SpoutException;
-use OpenSpout\Common\Helper\GlobalFunctionsHelper;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Writer\Common\Entity\Options;
-use OpenSpout\Writer\Exception\WriterAlreadyOpenedException;
-use OpenSpout\Writer\Exception\WriterNotOpenedException;
-
-abstract class WriterAbstract implements WriterInterface
-{
-    /** @var string Path to the output file */
-    protected $outputFilePath;
-
-    /** @var resource Pointer to the file/stream we will write to */
-    protected $filePointer;
-
-    /** @var bool Indicates whether the writer has been opened or not */
-    protected $isWriterOpened = false;
-
-    /** @var GlobalFunctionsHelper Helper to work with global functions */
-    protected $globalFunctionsHelper;
-
-    /** @var HelperFactory */
-    protected $helperFactory;
-
-    /** @var OptionsManagerInterface Writer options manager */
-    protected $optionsManager;
-
-    /** @var string Content-Type value for the header - to be defined by child class */
-    protected static $headerContentType;
-
-    public function __construct(
-        OptionsManagerInterface $optionsManager,
-        GlobalFunctionsHelper $globalFunctionsHelper,
-        HelperFactory $helperFactory
-    ) {
-        $this->optionsManager = $optionsManager;
-        $this->globalFunctionsHelper = $globalFunctionsHelper;
-        $this->helperFactory = $helperFactory;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function setDefaultRowStyle(Style $defaultStyle)
-    {
-        $this->optionsManager->setOption(Options::DEFAULT_ROW_STYLE, $defaultStyle);
-
-        return $this;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function openToFile($outputFilePath)
-    {
-        $this->outputFilePath = $outputFilePath;
-
-        $this->filePointer = $this->globalFunctionsHelper->fopen($this->outputFilePath, 'wb+');
-        $this->throwIfFilePointerIsNotAvailable();
-
-        $this->openWriter();
-        $this->isWriterOpened = true;
-
-        return $this;
-    }
-
-    /**
-     * @codeCoverageIgnore
-     * {@inheritdoc}
-     */
-    public function openToBrowser($outputFileName)
-    {
-        $this->outputFilePath = $this->globalFunctionsHelper->basename($outputFileName);
-
-        $this->filePointer = $this->globalFunctionsHelper->fopen('php://output', 'w');
-        $this->throwIfFilePointerIsNotAvailable();
-
-        // Clear any previous output (otherwise the generated file will be corrupted)
-        // @see https://github.com/box/spout/issues/241
-        $this->globalFunctionsHelper->ob_end_clean();
-
-        /*
-         * Set headers
-         *
-         * For newer browsers such as Firefox, Chrome, Opera, Safari, etc., they all support and use `filename*`
-         * specified by the new standard, even if they do not automatically decode filename; it does not matter;
-         * and for older versions of Internet Explorer, they are not recognized `filename*`, will automatically
-         * ignore it and use the old `filename` (the only minor flaw is that there must be an English suffix name).
-         * In this way, the multi-browser multi-language compatibility problem is perfectly solved, which does not
-         * require UA judgment and is more in line with the standard.
-         *
-         * @see https://github.com/box/spout/issues/745
-         * @see https://tools.ietf.org/html/rfc6266
-         * @see https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Content-Disposition
-         */
-        $this->globalFunctionsHelper->header('Content-Type: '.static::$headerContentType);
-        $this->globalFunctionsHelper->header(
-            'Content-Disposition: attachment; '.
-            'filename="'.rawurlencode($this->outputFilePath).'"; '.
-            'filename*=UTF-8\'\''.rawurlencode($this->outputFilePath)
-        );
-
-        /*
-         * When forcing the download of a file over SSL,IE8 and lower browsers fail
-         * if the Cache-Control and Pragma headers are not set.
-         *
-         * @see http://support.microsoft.com/KB/323308
-         * @see https://github.com/liuggio/ExcelBundle/issues/45
-         */
-        $this->globalFunctionsHelper->header('Cache-Control: max-age=0');
-        $this->globalFunctionsHelper->header('Pragma: public');
-
-        $this->openWriter();
-        $this->isWriterOpened = true;
-
-        return $this;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function addRow(Row $row)
-    {
-        if ($this->isWriterOpened) {
-            try {
-                $this->addRowToWriter($row);
-            } catch (SpoutException $e) {
-                // if an exception occurs while writing data,
-                // close the writer and remove all files created so far.
-                $this->closeAndAttemptToCleanupAllFiles();
-
-                // re-throw the exception to alert developers of the error
-                throw $e;
-            }
-        } else {
-            throw new WriterNotOpenedException('The writer needs to be opened before adding row.');
-        }
-
-        return $this;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function addRows(array $rows)
-    {
-        foreach ($rows as $row) {
-            if (!$row instanceof Row) {
-                $this->closeAndAttemptToCleanupAllFiles();
-
-                throw new InvalidArgumentException('The input should be an array of Row');
-            }
-
-            $this->addRow($row);
-        }
-
-        return $this;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function close()
-    {
-        if (!$this->isWriterOpened) {
-            return;
-        }
-
-        $this->closeWriter();
-
-        if (\is_resource($this->filePointer)) {
-            $this->globalFunctionsHelper->fclose($this->filePointer);
-        }
-
-        $this->isWriterOpened = false;
-    }
-
-    /**
-     * Opens the streamer and makes it ready to accept data.
-     *
-     * @throws IOException If the writer cannot be opened
-     */
-    abstract protected function openWriter();
-
-    /**
-     * Adds a row to the currently opened writer.
-     *
-     * @param Row $row The row containing cells and styles
-     *
-     * @throws WriterNotOpenedException If the workbook is not created yet
-     * @throws IOException              If unable to write data
-     */
-    abstract protected function addRowToWriter(Row $row);
-
-    /**
-     * Closes the streamer, preventing any additional writing.
-     */
-    abstract protected function closeWriter();
-
-    /**
-     * Checks if the pointer to the file/stream to write to is available.
-     * Will throw an exception if not available.
-     *
-     * @throws IOException If the pointer is not available
-     */
-    protected function throwIfFilePointerIsNotAvailable()
-    {
-        if (!\is_resource($this->filePointer)) {
-            throw new IOException('File pointer has not be opened');
-        }
-    }
-
-    /**
-     * Checks if the writer has already been opened, since some actions must be done before it gets opened.
-     * Throws an exception if already opened.
-     *
-     * @param string $message Error message
-     *
-     * @throws WriterAlreadyOpenedException if the writer was already opened and must not be
-     */
-    protected function throwIfWriterAlreadyOpened($message)
-    {
-        if ($this->isWriterOpened) {
-            throw new WriterAlreadyOpenedException($message);
-        }
-    }
-
-    /**
-     * Closes the writer and attempts to cleanup all files that were
-     * created during the writing process (temp files & final file).
-     */
-    private function closeAndAttemptToCleanupAllFiles()
-    {
-        // close the writer, which should remove all temp files
-        $this->close();
-
-        // remove output file if it was created
-        if ($this->globalFunctionsHelper->file_exists($this->outputFilePath)) {
-            $outputFolderPath = \dirname($this->outputFilePath);
-            $fileSystemHelper = $this->helperFactory->createFileSystemHelper($outputFolderPath);
-            $fileSystemHelper->deleteFile($this->outputFilePath);
-        }
-    }
-}
diff --git a/lib/openspout/src/Writer/WriterInterface.php b/lib/openspout/src/Writer/WriterInterface.php
index 71a298e6a73..ac43e33e4e8 100644
--- a/lib/openspout/src/Writer/WriterInterface.php
+++ b/lib/openspout/src/Writer/WriterInterface.php
@@ -1,13 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer;
 
 use OpenSpout\Common\Entity\Row;
-use OpenSpout\Common\Entity\Style\Style;
 
-/**
- * Interface WriterInterface.
- */
 interface WriterInterface
 {
     /**
@@ -17,10 +15,8 @@ interface WriterInterface
      * @param string $outputFilePath Path of the output file that will contain the data
      *
      * @throws \OpenSpout\Common\Exception\IOException If the writer cannot be opened or if the given path is not writable
-     *
-     * @return WriterInterface
      */
-    public function openToFile($outputFilePath);
+    public function openToFile(string $outputFilePath): void;
 
     /**
      * Initializes the writer and opens it to accept data.
@@ -29,20 +25,8 @@ interface WriterInterface
      * @param string $outputFileName Name of the output file that will contain the data. If a path is passed in, only the file name will be kept
      *
      * @throws \OpenSpout\Common\Exception\IOException If the writer cannot be opened
-     *
-     * @return WriterInterface
      */
-    public function openToBrowser($outputFileName);
-
-    /**
-     * Sets the default styles for all rows added with "addRow".
-     * Overriding the default style instead of using "addRowWithStyle" improves performance by 20%.
-     *
-     * @see https://github.com/box/spout/issues/272
-     *
-     * @return WriterInterface
-     */
-    public function setDefaultRowStyle(Style $defaultStyle);
+    public function openToBrowser(string $outputFileName): void;
 
     /**
      * Appends a row to the end of the stream.
@@ -51,10 +35,8 @@ interface WriterInterface
      *
      * @throws \OpenSpout\Writer\Exception\WriterNotOpenedException If the writer has not been opened yet
      * @throws \OpenSpout\Common\Exception\IOException              If unable to write data
-     *
-     * @return WriterInterface
      */
-    public function addRow(Row $row);
+    public function addRow(Row $row): void;
 
     /**
      * Appends the rows to the end of the stream.
@@ -64,14 +46,17 @@ interface WriterInterface
      * @throws \OpenSpout\Common\Exception\InvalidArgumentException If the input param is not valid
      * @throws \OpenSpout\Writer\Exception\WriterNotOpenedException If the writer has not been opened yet
      * @throws \OpenSpout\Common\Exception\IOException              If unable to write data
-     *
-     * @return WriterInterface
      */
-    public function addRows(array $rows);
+    public function addRows(array $rows): void;
+
+    /**
+     * @return 0|positive-int
+     */
+    public function getWrittenRowCount(): int;
 
     /**
      * Closes the writer. This will close the streamer as well, preventing new data
      * to be written to the file.
      */
-    public function close();
+    public function close(): void;
 }
diff --git a/lib/openspout/src/Writer/WriterMultiSheetsAbstract.php b/lib/openspout/src/Writer/WriterMultiSheetsAbstract.php
deleted file mode 100644
index 3c5f8d25012..00000000000
--- a/lib/openspout/src/Writer/WriterMultiSheetsAbstract.php
+++ /dev/null
@@ -1,216 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer;
-
-use OpenSpout\Common\Creator\HelperFactory;
-use OpenSpout\Common\Entity\Row;
-use OpenSpout\Common\Exception\IOException;
-use OpenSpout\Common\Helper\GlobalFunctionsHelper;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Writer\Common\Creator\ManagerFactoryInterface;
-use OpenSpout\Writer\Common\Entity\Options;
-use OpenSpout\Writer\Common\Entity\Sheet;
-use OpenSpout\Writer\Common\Manager\WorkbookManagerInterface;
-use OpenSpout\Writer\Exception\SheetNotFoundException;
-use OpenSpout\Writer\Exception\WriterAlreadyOpenedException;
-use OpenSpout\Writer\Exception\WriterNotOpenedException;
-
-abstract class WriterMultiSheetsAbstract extends WriterAbstract
-{
-    /** @var ManagerFactoryInterface */
-    private $managerFactory;
-
-    /** @var null|WorkbookManagerInterface */
-    private $workbookManager;
-
-    public function __construct(
-        OptionsManagerInterface $optionsManager,
-        GlobalFunctionsHelper $globalFunctionsHelper,
-        HelperFactory $helperFactory,
-        ManagerFactoryInterface $managerFactory
-    ) {
-        parent::__construct($optionsManager, $globalFunctionsHelper, $helperFactory);
-        $this->managerFactory = $managerFactory;
-    }
-
-    /**
-     * Sets whether new sheets should be automatically created when the max rows limit per sheet is reached.
-     * This must be set before opening the writer.
-     *
-     * @param bool $shouldCreateNewSheetsAutomatically Whether new sheets should be automatically created when the max rows limit per sheet is reached
-     *
-     * @throws WriterAlreadyOpenedException If the writer was already opened
-     *
-     * @return WriterMultiSheetsAbstract
-     */
-    public function setShouldCreateNewSheetsAutomatically($shouldCreateNewSheetsAutomatically)
-    {
-        $this->throwIfWriterAlreadyOpened('Writer must be configured before opening it.');
-
-        $this->optionsManager->setOption(
-            Options::SHOULD_CREATE_NEW_SHEETS_AUTOMATICALLY,
-            $shouldCreateNewSheetsAutomatically
-        );
-
-        return $this;
-    }
-
-    /**
-     * Returns all the workbook's sheets.
-     *
-     * @throws WriterNotOpenedException If the writer has not been opened yet
-     *
-     * @return Sheet[] All the workbook's sheets
-     */
-    public function getSheets()
-    {
-        $this->throwIfWorkbookIsNotAvailable();
-
-        $externalSheets = [];
-        $worksheets = $this->workbookManager->getWorksheets();
-
-        foreach ($worksheets as $worksheet) {
-            $externalSheets[] = $worksheet->getExternalSheet();
-        }
-
-        return $externalSheets;
-    }
-
-    /**
-     * Creates a new sheet and make it the current sheet. The data will now be written to this sheet.
-     *
-     * @throws IOException
-     * @throws WriterNotOpenedException If the writer has not been opened yet
-     *
-     * @return Sheet The created sheet
-     */
-    public function addNewSheetAndMakeItCurrent()
-    {
-        $this->throwIfWorkbookIsNotAvailable();
-        $worksheet = $this->workbookManager->addNewSheetAndMakeItCurrent();
-
-        return $worksheet->getExternalSheet();
-    }
-
-    /**
-     * Returns the current sheet.
-     *
-     * @throws WriterNotOpenedException If the writer has not been opened yet
-     *
-     * @return Sheet The current sheet
-     */
-    public function getCurrentSheet()
-    {
-        $this->throwIfWorkbookIsNotAvailable();
-
-        return $this->workbookManager->getCurrentWorksheet()->getExternalSheet();
-    }
-
-    /**
-     * Sets the given sheet as the current one. New data will be written to this sheet.
-     * The writing will resume where it stopped (i.e. data won't be truncated).
-     *
-     * @param Sheet $sheet The sheet to set as current
-     *
-     * @throws SheetNotFoundException   If the given sheet does not exist in the workbook
-     * @throws WriterNotOpenedException If the writer has not been opened yet
-     */
-    public function setCurrentSheet($sheet)
-    {
-        $this->throwIfWorkbookIsNotAvailable();
-        $this->workbookManager->setCurrentSheet($sheet);
-    }
-
-    /**
-     * @throws WriterAlreadyOpenedException
-     */
-    public function setDefaultColumnWidth(float $width)
-    {
-        $this->throwIfWriterAlreadyOpened('Writer must be configured before opening it.');
-        $this->optionsManager->setOption(
-            Options::DEFAULT_COLUMN_WIDTH,
-            $width
-        );
-    }
-
-    /**
-     * @throws WriterAlreadyOpenedException
-     */
-    public function setDefaultRowHeight(float $height)
-    {
-        $this->throwIfWriterAlreadyOpened('Writer must be configured before opening it.');
-        $this->optionsManager->setOption(
-            Options::DEFAULT_ROW_HEIGHT,
-            $height
-        );
-    }
-
-    /**
-     * @param null|float $width
-     * @param int        ...$columns One or more columns with this width
-     *
-     * @throws WriterNotOpenedException
-     */
-    public function setColumnWidth($width, ...$columns)
-    {
-        $this->throwIfWorkbookIsNotAvailable();
-        $this->workbookManager->setColumnWidth($width, ...$columns);
-    }
-
-    /**
-     * @param float $width The width to set
-     * @param int   $start First column index of the range
-     * @param int   $end   Last column index of the range
-     *
-     * @throws WriterNotOpenedException
-     */
-    public function setColumnWidthForRange(float $width, int $start, int $end)
-    {
-        $this->throwIfWorkbookIsNotAvailable();
-        $this->workbookManager->setColumnWidthForRange($width, $start, $end);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function openWriter()
-    {
-        if (null === $this->workbookManager) {
-            $this->workbookManager = $this->managerFactory->createWorkbookManager($this->optionsManager);
-            $this->workbookManager->addNewSheetAndMakeItCurrent();
-        }
-    }
-
-    /**
-     * Checks if the workbook has been created. Throws an exception if not created yet.
-     *
-     * @throws WriterNotOpenedException If the workbook is not created yet
-     */
-    protected function throwIfWorkbookIsNotAvailable()
-    {
-        if (!$this->workbookManager->getWorkbook()) {
-            throw new WriterNotOpenedException('The writer must be opened before performing this action.');
-        }
-    }
-
-    /**
-     * {@inheritdoc}
-     *
-     * @throws Exception\WriterException
-     */
-    protected function addRowToWriter(Row $row)
-    {
-        $this->throwIfWorkbookIsNotAvailable();
-        $this->workbookManager->addRowToCurrentWorksheet($row);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function closeWriter()
-    {
-        if (null !== $this->workbookManager) {
-            $this->workbookManager->close($this->filePointer);
-        }
-    }
-}
diff --git a/lib/openspout/src/Writer/XLSX/Creator/HelperFactory.php b/lib/openspout/src/Writer/XLSX/Creator/HelperFactory.php
deleted file mode 100644
index 38a7f0daf6a..00000000000
--- a/lib/openspout/src/Writer/XLSX/Creator/HelperFactory.php
+++ /dev/null
@@ -1,53 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\XLSX\Creator;
-
-use OpenSpout\Common\Helper\Escaper;
-use OpenSpout\Common\Helper\StringHelper;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Writer\Common\Creator\InternalEntityFactory;
-use OpenSpout\Writer\Common\Entity\Options;
-use OpenSpout\Writer\Common\Helper\ZipHelper;
-use OpenSpout\Writer\XLSX\Helper\FileSystemHelper;
-
-/**
- * Factory for helpers needed by the XLSX Writer.
- */
-class HelperFactory extends \OpenSpout\Common\Creator\HelperFactory
-{
-    /**
-     * @return FileSystemHelper
-     */
-    public function createSpecificFileSystemHelper(OptionsManagerInterface $optionsManager, InternalEntityFactory $entityFactory)
-    {
-        $tempFolder = $optionsManager->getOption(Options::TEMP_FOLDER);
-        $zipHelper = $this->createZipHelper($entityFactory);
-        $escaper = $this->createStringsEscaper();
-
-        return new FileSystemHelper($tempFolder, $zipHelper, $escaper);
-    }
-
-    /**
-     * @return Escaper\XLSX
-     */
-    public function createStringsEscaper()
-    {
-        return new Escaper\XLSX();
-    }
-
-    /**
-     * @return StringHelper
-     */
-    public function createStringHelper()
-    {
-        return new StringHelper();
-    }
-
-    /**
-     * @return ZipHelper
-     */
-    private function createZipHelper(InternalEntityFactory $entityFactory)
-    {
-        return new ZipHelper($entityFactory);
-    }
-}
diff --git a/lib/openspout/src/Writer/XLSX/Creator/ManagerFactory.php b/lib/openspout/src/Writer/XLSX/Creator/ManagerFactory.php
deleted file mode 100644
index 47e60ce49b9..00000000000
--- a/lib/openspout/src/Writer/XLSX/Creator/ManagerFactory.php
+++ /dev/null
@@ -1,145 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\XLSX\Creator;
-
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Writer\Common\Creator\InternalEntityFactory;
-use OpenSpout\Writer\Common\Creator\ManagerFactoryInterface;
-use OpenSpout\Writer\Common\Entity\Options;
-use OpenSpout\Writer\Common\Manager\RowManager;
-use OpenSpout\Writer\Common\Manager\SheetManager;
-use OpenSpout\Writer\Common\Manager\Style\StyleMerger;
-use OpenSpout\Writer\XLSX\Manager\SharedStringsManager;
-use OpenSpout\Writer\XLSX\Manager\Style\StyleManager;
-use OpenSpout\Writer\XLSX\Manager\Style\StyleRegistry;
-use OpenSpout\Writer\XLSX\Manager\WorkbookManager;
-use OpenSpout\Writer\XLSX\Manager\WorksheetManager;
-
-/**
- * Factory for managers needed by the XLSX Writer.
- */
-class ManagerFactory implements ManagerFactoryInterface
-{
-    /** @var InternalEntityFactory */
-    protected $entityFactory;
-
-    /** @var HelperFactory */
-    protected $helperFactory;
-
-    public function __construct(InternalEntityFactory $entityFactory, HelperFactory $helperFactory)
-    {
-        $this->entityFactory = $entityFactory;
-        $this->helperFactory = $helperFactory;
-    }
-
-    /**
-     * @return WorkbookManager
-     */
-    public function createWorkbookManager(OptionsManagerInterface $optionsManager)
-    {
-        $workbook = $this->entityFactory->createWorkbook();
-
-        $fileSystemHelper = $this->helperFactory->createSpecificFileSystemHelper($optionsManager, $this->entityFactory);
-        $fileSystemHelper->createBaseFilesAndFolders();
-
-        $xlFolder = $fileSystemHelper->getXlFolder();
-        $sharedStringsManager = $this->createSharedStringsManager($xlFolder);
-
-        $styleMerger = $this->createStyleMerger();
-        $styleManager = $this->createStyleManager($optionsManager);
-        $worksheetManager = $this->createWorksheetManager($optionsManager, $styleManager, $styleMerger, $sharedStringsManager);
-
-        return new WorkbookManager(
-            $workbook,
-            $optionsManager,
-            $worksheetManager,
-            $styleManager,
-            $styleMerger,
-            $fileSystemHelper,
-            $this->entityFactory,
-            $this
-        );
-    }
-
-    /**
-     * @return SheetManager
-     */
-    public function createSheetManager()
-    {
-        $stringHelper = $this->helperFactory->createStringHelper();
-
-        return new SheetManager($stringHelper);
-    }
-
-    /**
-     * @return RowManager
-     */
-    public function createRowManager()
-    {
-        return new RowManager();
-    }
-
-    /**
-     * @return WorksheetManager
-     */
-    private function createWorksheetManager(
-        OptionsManagerInterface $optionsManager,
-        StyleManager $styleManager,
-        StyleMerger $styleMerger,
-        SharedStringsManager $sharedStringsManager
-    ) {
-        $rowManager = $this->createRowManager();
-        $stringsEscaper = $this->helperFactory->createStringsEscaper();
-        $stringsHelper = $this->helperFactory->createStringHelper();
-
-        return new WorksheetManager(
-            $optionsManager,
-            $rowManager,
-            $styleManager,
-            $styleMerger,
-            $sharedStringsManager,
-            $stringsEscaper,
-            $stringsHelper
-        );
-    }
-
-    /**
-     * @return StyleManager
-     */
-    private function createStyleManager(OptionsManagerInterface $optionsManager)
-    {
-        $styleRegistry = $this->createStyleRegistry($optionsManager);
-
-        return new StyleManager($styleRegistry);
-    }
-
-    /**
-     * @return StyleRegistry
-     */
-    private function createStyleRegistry(OptionsManagerInterface $optionsManager)
-    {
-        $defaultRowStyle = $optionsManager->getOption(Options::DEFAULT_ROW_STYLE);
-
-        return new StyleRegistry($defaultRowStyle);
-    }
-
-    /**
-     * @return StyleMerger
-     */
-    private function createStyleMerger()
-    {
-        return new StyleMerger();
-    }
-
-    /**
-     * @param string $xlFolder Path to the "xl" folder
-     *
-     * @return SharedStringsManager
-     */
-    private function createSharedStringsManager($xlFolder)
-    {
-        $stringEscaper = $this->helperFactory->createStringsEscaper();
-
-        return new SharedStringsManager($xlFolder, $stringEscaper);
-    }
-}
diff --git a/lib/openspout/src/Writer/XLSX/Entity/SheetView.php b/lib/openspout/src/Writer/XLSX/Entity/SheetView.php
index 71416159242..4cbd400006b 100644
--- a/lib/openspout/src/Writer/XLSX/Entity/SheetView.php
+++ b/lib/openspout/src/Writer/XLSX/Entity/SheetView.php
@@ -1,62 +1,31 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\XLSX\Entity;
 
 use OpenSpout\Common\Exception\InvalidArgumentException;
 use OpenSpout\Reader\XLSX\Helper\CellHelper;
 
-class SheetView
+final class SheetView
 {
-    /** @var bool */
-    protected $showFormulas = false;
-
-    /** @var bool */
-    protected $showGridLines = true;
-
-    /** @var bool */
-    protected $showRowColHeaders = true;
-
-    /** @var bool */
-    protected $showZeroes = true;
-
-    /** @var bool */
-    protected $rightToLeft = false;
-
-    /** @var bool */
-    protected $tabSelected = false;
-
-    /** @var bool */
-    protected $showOutlineSymbols = true;
-
-    /** @var bool */
-    protected $defaultGridColor = true;
-
-    /** @var string */
-    protected $view = 'normal';
-
-    /** @var string */
-    protected $topLeftCell = 'A1';
-
-    /** @var int */
-    protected $colorId = 64;
-
-    /** @var int */
-    protected $zoomScale = 100;
-
-    /** @var int */
-    protected $zoomScaleNormal = 100;
-
-    /** @var int */
-    protected $zoomScalePageLayoutView = 100;
-
-    /** @var int */
-    protected $workbookViewId = 0;
-
-    /** @var int */
-    protected $freezeRow = 0;
-
-    /** @var string */
-    protected $freezeColumn = 'A';
+    private bool $showFormulas = false;
+    private bool $showGridLines = true;
+    private bool $showRowColHeaders = true;
+    private bool $showZeroes = true;
+    private bool $rightToLeft = false;
+    private bool $tabSelected = false;
+    private bool $showOutlineSymbols = true;
+    private bool $defaultGridColor = true;
+    private string $view = 'normal';
+    private string $topLeftCell = 'A1';
+    private int $colorId = 64;
+    private int $zoomScale = 100;
+    private int $zoomScaleNormal = 100;
+    private int $zoomScalePageLayoutView = 100;
+    private int $workbookViewId = 0;
+    private int $freezeRow = 0;
+    private string $freezeColumn = 'A';
 
     /**
      * @return $this
@@ -209,14 +178,14 @@ class SheetView
     }
 
     /**
-     * @param int $freezeRow Set to 2 to fix the first row
+     * @param positive-int $freezeRow Set to 2 to fix the first row
      *
      * @return $this
      */
     public function setFreezeRow(int $freezeRow): self
     {
         if ($freezeRow < 1) {
-            throw new InvalidArgumentException('Freeze row must be a positive integer', 1589543073);
+            throw new InvalidArgumentException('Freeze row must be a positive integer');
         }
 
         $this->freezeRow = $freezeRow;
@@ -243,16 +212,28 @@ class SheetView
         '</sheetView>';
     }
 
-    protected function getSheetViewAttributes(): string
+    private function getSheetViewAttributes(): string
     {
-        // Get class properties
-        $propertyValues = get_object_vars($this);
-        unset($propertyValues['freezeRow'], $propertyValues['freezeColumn']);
-
-        return $this->generateAttributes($propertyValues);
+        return $this->generateAttributes([
+            'showFormulas' => $this->showFormulas,
+            'showGridLines' => $this->showGridLines,
+            'showRowColHeaders' => $this->showRowColHeaders,
+            'showZeroes' => $this->showZeroes,
+            'rightToLeft' => $this->rightToLeft,
+            'tabSelected' => $this->tabSelected,
+            'showOutlineSymbols' => $this->showOutlineSymbols,
+            'defaultGridColor' => $this->defaultGridColor,
+            'view' => $this->view,
+            'topLeftCell' => $this->topLeftCell,
+            'colorId' => $this->colorId,
+            'zoomScale' => $this->zoomScale,
+            'zoomScaleNormal' => $this->zoomScaleNormal,
+            'zoomScalePageLayoutView' => $this->zoomScalePageLayoutView,
+            'workbookViewId' => $this->workbookViewId,
+        ]);
     }
 
-    protected function getFreezeCellPaneXml(): string
+    private function getFreezeCellPaneXml(): string
     {
         if ($this->freezeRow < 2 && 'A' === $this->freezeColumn) {
             return '';
@@ -270,12 +251,12 @@ class SheetView
     }
 
     /**
-     * @param array $data with key containing the attribute name and value containing the attribute value
+     * @param array<string, bool|int|string> $data with key containing the attribute name and value containing the attribute value
      */
-    protected function generateAttributes(array $data): string
+    private function generateAttributes(array $data): string
     {
         // Create attribute for each key
-        $attributes = array_map(function ($key, $value) {
+        $attributes = array_map(static function (string $key, bool|string|int $value): string {
             if (\is_bool($value)) {
                 $value = $value ? 'true' : 'false';
             }
diff --git a/lib/openspout/src/Writer/XLSX/Helper/BorderHelper.php b/lib/openspout/src/Writer/XLSX/Helper/BorderHelper.php
index 1df43b9f105..dff73459f12 100644
--- a/lib/openspout/src/Writer/XLSX/Helper/BorderHelper.php
+++ b/lib/openspout/src/Writer/XLSX/Helper/BorderHelper.php
@@ -1,13 +1,18 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\XLSX\Helper;
 
 use OpenSpout\Common\Entity\Style\Border;
 use OpenSpout\Common\Entity\Style\BorderPart;
 
-class BorderHelper
+/**
+ * @internal
+ */
+final class BorderHelper
 {
-    public static $xlsxStyleMap = [
+    private const xlsxStyleMap = [
         Border::STYLE_SOLID => [
             Border::WIDTH_THIN => 'thin',
             Border::WIDTH_MEDIUM => 'medium',
@@ -35,14 +40,15 @@ class BorderHelper
         ],
     ];
 
-    /**
-     * @return string
-     */
-    public static function serializeBorderPart(BorderPart $borderPart)
+    public static function serializeBorderPart(?BorderPart $borderPart): string
     {
+        if (null === $borderPart) {
+            return '';
+        }
+
         $borderStyle = self::getBorderStyle($borderPart);
 
-        $colorEl = $borderPart->getColor() ? sprintf('<color rgb="%s"/>', $borderPart->getColor()) : '';
+        $colorEl = sprintf('<color rgb="%s"/>', $borderPart->getColor());
         $partEl = sprintf(
             '<%s style="%s">%s</%s>',
             $borderPart->getName(),
@@ -56,11 +62,9 @@ class BorderHelper
 
     /**
      * Get the style definition from the style map.
-     *
-     * @return string
      */
-    protected static function getBorderStyle(BorderPart $borderPart)
+    private static function getBorderStyle(BorderPart $borderPart): string
     {
-        return self::$xlsxStyleMap[$borderPart->getStyle()][$borderPart->getWidth()];
+        return self::xlsxStyleMap[$borderPart->getStyle()][$borderPart->getWidth()];
     }
 }
diff --git a/lib/openspout/src/Writer/XLSX/Helper/DateHelper.php b/lib/openspout/src/Writer/XLSX/Helper/DateHelper.php
index fb72df534d4..b18a9453157 100644
--- a/lib/openspout/src/Writer/XLSX/Helper/DateHelper.php
+++ b/lib/openspout/src/Writer/XLSX/Helper/DateHelper.php
@@ -1,15 +1,20 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\XLSX\Helper;
 
-class DateHelper
+use DateTimeInterface;
+
+/**
+ * @internal
+ */
+final class DateHelper
 {
     /**
      * @see https://github.com/PHPOffice/PhpSpreadsheet/blob/1.22.0/src/PhpSpreadsheet/Shared/Date.php#L296
-     *
-     * @return float
      */
-    public static function toExcel(\DateTimeInterface $dateTime)
+    public static function toExcel(DateTimeInterface $dateTime): float
     {
         $year = (int) $dateTime->format('Y');
         $month = (int) $dateTime->format('m');
@@ -19,9 +24,9 @@ class DateHelper
         $seconds = (int) $dateTime->format('s');
         // Fudge factor for the erroneous fact that the year 1900 is treated as a Leap Year in MS Excel
         // This affects every date following 28th February 1900
-        $excel1900isLeapYear = true;
+        $excel1900isLeapYear = 1;
         if ((1900 === $year) && ($month <= 2)) {
-            $excel1900isLeapYear = false;
+            $excel1900isLeapYear = 0;
         }
         $myexcelBaseDate = 2415020;
 
@@ -36,10 +41,18 @@ class DateHelper
         //    Calculate the Julian Date, then subtract the Excel base date (JD 2415020 = 31-Dec-1899 Giving Excel Date of 0)
         $century = (int) substr((string) $year, 0, 2);
         $decade = (int) substr((string) $year, 2, 2);
-        $excelDate = floor((146097 * $century) / 4) + floor((1461 * $decade) / 4) + floor((153 * $month + 2) / 5) + $day + 1721119 - $myexcelBaseDate + $excel1900isLeapYear;
+        $excelDate =
+            floor((146097 * $century) / 4)
+            + floor((1461 * $decade) / 4)
+            + floor((153 * $month + 2) / 5)
+            + $day
+            + 1721119
+            - $myexcelBaseDate
+            + $excel1900isLeapYear
+        ;
 
         $excelTime = (($hours * 3600) + ($minutes * 60) + $seconds) / 86400;
 
-        return (float) $excelDate + $excelTime;
+        return $excelDate + $excelTime;
     }
 }
diff --git a/lib/openspout/src/Writer/XLSX/Helper/FileSystemHelper.php b/lib/openspout/src/Writer/XLSX/Helper/FileSystemHelper.php
index 12e4d79c140..9a1e7174144 100644
--- a/lib/openspout/src/Writer/XLSX/Helper/FileSystemHelper.php
+++ b/lib/openspout/src/Writer/XLSX/Helper/FileSystemHelper.php
@@ -1,21 +1,30 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\XLSX\Helper;
 
+use DateTimeImmutable;
+use OpenSpout\Common\Helper\Escaper\XLSX;
+use OpenSpout\Common\Helper\FileSystemHelper as CommonFileSystemHelper;
+use OpenSpout\Writer\Common\Entity\Sheet;
 use OpenSpout\Writer\Common\Entity\Worksheet;
+use OpenSpout\Writer\Common\Helper\CellHelper;
 use OpenSpout\Writer\Common\Helper\FileSystemWithRootFolderHelperInterface;
 use OpenSpout\Writer\Common\Helper\ZipHelper;
 use OpenSpout\Writer\XLSX\Manager\Style\StyleManager;
+use OpenSpout\Writer\XLSX\MergeCell;
+use OpenSpout\Writer\XLSX\Options;
 
 /**
- * This class provides helper functions to help with the file system operations
- * like files/folders creation & deletion for XLSX files.
+ * @internal
  */
-class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper implements FileSystemWithRootFolderHelperInterface
+final class FileSystemHelper implements FileSystemWithRootFolderHelperInterface
 {
-    public const APP_NAME = 'Spout';
+    public const APP_NAME = 'OpenSpout';
 
     public const RELS_FOLDER_NAME = '_rels';
+    public const DRAWINGS_FOLDER_NAME = 'drawings';
     public const DOC_PROPS_FOLDER_NAME = 'docProps';
     public const XL_FOLDER_NAME = 'xl';
     public const WORKSHEETS_FOLDER_NAME = 'worksheets';
@@ -28,78 +37,107 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
     public const WORKBOOK_RELS_XML_FILE_NAME = 'workbook.xml.rels';
     public const STYLES_XML_FILE_NAME = 'styles.xml';
 
-    /** @var ZipHelper Helper to perform tasks with Zip archive */
-    private $zipHelper;
+    private const SHEET_XML_FILE_HEADER = <<<'EOD'
+        <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+        <worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships">
+        EOD;
 
-    /** @var \OpenSpout\Common\Helper\Escaper\XLSX Used to escape XML data */
-    private $escaper;
+    private string $baseFolderRealPath;
+    private CommonFileSystemHelper $baseFileSystemHelper;
+
+    /** @var ZipHelper Helper to perform tasks with Zip archive */
+    private ZipHelper $zipHelper;
+
+    /** @var XLSX Used to escape XML data */
+    private XLSX $escaper;
 
     /** @var string Path to the root folder inside the temp folder where the files to create the XLSX will be stored */
-    private $rootFolder;
+    private string $rootFolder;
 
     /** @var string Path to the "_rels" folder inside the root folder */
-    private $relsFolder;
+    private string $relsFolder;
 
     /** @var string Path to the "docProps" folder inside the root folder */
-    private $docPropsFolder;
+    private string $docPropsFolder;
 
     /** @var string Path to the "xl" folder inside the root folder */
-    private $xlFolder;
+    private string $xlFolder;
 
     /** @var string Path to the "_rels" folder inside the "xl" folder */
-    private $xlRelsFolder;
+    private string $xlRelsFolder;
 
     /** @var string Path to the "worksheets" folder inside the "xl" folder */
-    private $xlWorksheetsFolder;
+    private string $xlWorksheetsFolder;
+
+    /** @var string Path to the temp folder, inside the root folder, where specific sheets content will be written to */
+    private string $sheetsContentTempFolder;
 
     /**
-     * @param string                                $baseFolderPath The path of the base folder where all the I/O can occur
-     * @param ZipHelper                             $zipHelper      Helper to perform tasks with Zip archive
-     * @param \OpenSpout\Common\Helper\Escaper\XLSX $escaper        Used to escape XML data
+     * @param string    $baseFolderPath The path of the base folder where all the I/O can occur
+     * @param ZipHelper $zipHelper      Helper to perform tasks with Zip archive
+     * @param XLSX      $escaper        Used to escape XML data
      */
-    public function __construct($baseFolderPath, $zipHelper, $escaper)
+    public function __construct(string $baseFolderPath, ZipHelper $zipHelper, XLSX $escaper)
     {
-        parent::__construct($baseFolderPath);
+        $this->baseFileSystemHelper = new CommonFileSystemHelper($baseFolderPath);
+        $this->baseFolderRealPath = $this->baseFileSystemHelper->getBaseFolderRealPath();
         $this->zipHelper = $zipHelper;
         $this->escaper = $escaper;
     }
 
-    /**
-     * @return string
-     */
-    public function getRootFolder()
+    public function createFolder(string $parentFolderPath, string $folderName): string
+    {
+        return $this->baseFileSystemHelper->createFolder($parentFolderPath, $folderName);
+    }
+
+    public function createFileWithContents(string $parentFolderPath, string $fileName, string $fileContents): string
+    {
+        return $this->baseFileSystemHelper->createFileWithContents($parentFolderPath, $fileName, $fileContents);
+    }
+
+    public function deleteFile(string $filePath): void
+    {
+        $this->baseFileSystemHelper->deleteFile($filePath);
+    }
+
+    public function deleteFolderRecursively(string $folderPath): void
+    {
+        $this->baseFileSystemHelper->deleteFolderRecursively($folderPath);
+    }
+
+    public function getRootFolder(): string
     {
         return $this->rootFolder;
     }
 
-    /**
-     * @return string
-     */
-    public function getXlFolder()
+    public function getXlFolder(): string
     {
         return $this->xlFolder;
     }
 
-    /**
-     * @return string
-     */
-    public function getXlWorksheetsFolder()
+    public function getXlWorksheetsFolder(): string
     {
         return $this->xlWorksheetsFolder;
     }
 
+    public function getSheetsContentTempFolder(): string
+    {
+        return $this->sheetsContentTempFolder;
+    }
+
     /**
      * Creates all the folders needed to create a XLSX file, as well as the files that won't change.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create at least one of the base folders
      */
-    public function createBaseFilesAndFolders()
+    public function createBaseFilesAndFolders(): void
     {
         $this
             ->createRootFolder()
             ->createRelsFolderAndFile()
             ->createDocPropsFolderAndFiles()
             ->createXlFolderAndSubFolders()
+            ->createSheetsContentTempFolder()
         ;
     }
 
@@ -107,22 +145,22 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "[Content_Types].xml" file under the root folder.
      *
      * @param Worksheet[] $worksheets
-     *
-     * @return FileSystemHelper
      */
-    public function createContentTypesFile($worksheets)
+    public function createContentTypesFile(array $worksheets): self
     {
         $contentTypesXmlFileContents = <<<'EOD'
             <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
             <Types xmlns="http://schemas.openxmlformats.org/package/2006/content-types">
                 <Default ContentType="application/xml" Extension="xml"/>
                 <Default ContentType="application/vnd.openxmlformats-package.relationships+xml" Extension="rels"/>
+                <Default ContentType="application/vnd.openxmlformats-officedocument.vmlDrawing" Extension="vml"/>
                 <Override ContentType="application/vnd.openxmlformats-officedocument.spreadsheetml.sheet.main+xml" PartName="/xl/workbook.xml"/>
             EOD;
 
         /** @var Worksheet $worksheet */
         foreach ($worksheets as $worksheet) {
             $contentTypesXmlFileContents .= '<Override ContentType="application/vnd.openxmlformats-officedocument.spreadsheetml.worksheet+xml" PartName="/xl/worksheets/sheet'.$worksheet->getId().'.xml"/>';
+            $contentTypesXmlFileContents .= '<Override ContentType="application/vnd.openxmlformats-officedocument.spreadsheetml.comments+xml" PartName="/xl/comments'.$worksheet->getId().'.xml" />';
         }
 
         $contentTypesXmlFileContents .= <<<'EOD'
@@ -142,10 +180,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "workbook.xml" file under the "xl" folder.
      *
      * @param Worksheet[] $worksheets
-     *
-     * @return FileSystemHelper
      */
-    public function createWorkbookFile($worksheets)
+    public function createWorkbookFile(array $worksheets): self
     {
         $workbookXmlFileContents = <<<'EOD'
             <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
@@ -163,6 +199,31 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
 
         $workbookXmlFileContents .= <<<'EOD'
                 </sheets>
+            EOD;
+
+        $definedNames = '';
+
+        /** @var Worksheet $worksheet */
+        foreach ($worksheets as $worksheet) {
+            $sheet = $worksheet->getExternalSheet();
+            if (null !== $autofilter = $sheet->getAutoFilter()) {
+                $worksheetName = $sheet->getName();
+                $name = sprintf(
+                    '\'%s\'!$%s$%s:$%s$%s',
+                    $this->escaper->escape($worksheetName),
+                    CellHelper::getColumnLettersFromColumnIndex($autofilter->fromColumnIndex),
+                    $autofilter->fromRow,
+                    CellHelper::getColumnLettersFromColumnIndex($autofilter->toColumnIndex),
+                    $autofilter->toRow
+                );
+                $definedNames .= '<definedName function="false" hidden="true" localSheetId="'.$sheet->getIndex().'" name="_xlnm._FilterDatabase" vbProcedure="false">'.$name.'</definedName>';
+            }
+        }
+        if ('' !== $definedNames) {
+            $workbookXmlFileContents .= '<definedNames>'.$definedNames.'</definedNames>';
+        }
+
+        $workbookXmlFileContents .= <<<'EOD'
             </workbook>
             EOD;
 
@@ -175,10 +236,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "workbook.xml.res" file under the "xl/_res" folder.
      *
      * @param Worksheet[] $worksheets
-     *
-     * @return FileSystemHelper
      */
-    public function createWorkbookRelsFile($worksheets)
+    public function createWorkbookRelsFile(array $worksheets): self
     {
         $workbookRelsXmlFileContents = <<<'EOD'
             <?xml version="1.0" encoding="UTF-8"?>
@@ -201,13 +260,35 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
     }
 
     /**
-     * Creates the "styles.xml" file under the "xl" folder.
+     * Create the "rels" file for a given worksheet. This contains relations to the comments.xml and drawing.vml files for this worksheet.
      *
-     * @param StyleManager $styleManager
-     *
-     * @return FileSystemHelper
+     * @param Worksheet[] $worksheets
      */
-    public function createStylesFile($styleManager)
+    public function createWorksheetRelsFiles(array $worksheets): self
+    {
+        $this->createFolder($this->getXlWorksheetsFolder(), self::RELS_FOLDER_NAME);
+
+        foreach ($worksheets as $worksheet) {
+            $worksheetId = $worksheet->getId();
+            $worksheetRelsContent = '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+              <Relationships xmlns="http://schemas.openxmlformats.org/package/2006/relationships">
+                <Relationship Id="rId_comments_vml1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/vmlDrawing" Target="../drawings/vmlDrawing'.$worksheetId.'.vml"/>
+                <Relationship Id="rId_comments1" Type="http://schemas.openxmlformats.org/officeDocument/2006/relationships/comments" Target="../comments'.$worksheetId.'.xml"/>
+              </Relationships>';
+
+            $folder = $this->getXlWorksheetsFolder().\DIRECTORY_SEPARATOR.'_rels';
+            $filename = 'sheet'.$worksheetId.'.xml.rels';
+
+            $this->createFileWithContents($folder, $filename, $worksheetRelsContent);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Creates the "styles.xml" file under the "xl" folder.
+     */
+    public function createStylesFile(StyleManager $styleManager): self
     {
         $stylesXmlFileContents = $styleManager->getStylesXMLFileContent();
         $this->createFileWithContents($this->xlFolder, self::STYLES_XML_FILE_NAME, $stylesXmlFileContents);
@@ -215,12 +296,99 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
         return $this;
     }
 
+    /**
+     * Creates the "content.xml" file under the root folder.
+     *
+     * @param Worksheet[] $worksheets
+     */
+    public function createContentFiles(Options $options, array $worksheets): self
+    {
+        $allMergeCells = $options->getMergeCells();
+
+        foreach ($worksheets as $worksheet) {
+            $contentXmlFilePath = $this->getXlWorksheetsFolder().\DIRECTORY_SEPARATOR.basename($worksheet->getFilePath());
+            $worksheetFilePointer = fopen($contentXmlFilePath, 'w');
+            \assert(false !== $worksheetFilePointer);
+
+            $sheet = $worksheet->getExternalSheet();
+            fwrite($worksheetFilePointer, self::SHEET_XML_FILE_HEADER);
+
+            // AutoFilter tags
+            $range = '';
+            if (null !== $autofilter = $sheet->getAutoFilter()) {
+                $range = sprintf(
+                    '%s%s:%s%s',
+                    CellHelper::getColumnLettersFromColumnIndex($autofilter->fromColumnIndex),
+                    $autofilter->fromRow,
+                    CellHelper::getColumnLettersFromColumnIndex($autofilter->toColumnIndex),
+                    $autofilter->toRow
+                );
+                fwrite($worksheetFilePointer, '<sheetPr filterMode="false"><pageSetUpPr fitToPage="false"/></sheetPr>');
+                fwrite($worksheetFilePointer, sprintf('<dimension ref="%s"/>', $range));
+            }
+
+            if (null !== ($sheetView = $sheet->getSheetView())) {
+                fwrite($worksheetFilePointer, '<sheetViews>'.$sheetView->getXml().'</sheetViews>');
+            }
+            fwrite($worksheetFilePointer, $this->getXMLFragmentForDefaultCellSizing($options));
+            fwrite($worksheetFilePointer, $this->getXMLFragmentForColumnWidths($options, $sheet));
+            fwrite($worksheetFilePointer, '<sheetData>');
+
+            $worksheetFilePath = $worksheet->getFilePath();
+            $this->copyFileContentsToTarget($worksheetFilePath, $worksheetFilePointer);
+            fwrite($worksheetFilePointer, '</sheetData>');
+
+            // AutoFilter tag
+            if ('' !== $range) {
+                fwrite($worksheetFilePointer, sprintf('<autoFilter ref="%s"/>', $range));
+            }
+
+            // create nodes for merge cells
+            $mergeCells = array_filter(
+                $allMergeCells,
+                static fn (MergeCell $c) => $c->sheetIndex === $worksheet->getExternalSheet()->getIndex(),
+            );
+            if ([] !== $mergeCells) {
+                $mergeCellString = '<mergeCells count="'.\count($mergeCells).'">';
+                foreach ($mergeCells as $mergeCell) {
+                    $topLeft = CellHelper::getColumnLettersFromColumnIndex($mergeCell->topLeftColumn).$mergeCell->topLeftRow;
+                    $bottomRight = CellHelper::getColumnLettersFromColumnIndex($mergeCell->bottomRightColumn).$mergeCell->bottomRightRow;
+                    $mergeCellString .= sprintf(
+                        '<mergeCell ref="%s:%s"/>',
+                        $topLeft,
+                        $bottomRight
+                    );
+                }
+                $mergeCellString .= '</mergeCells>';
+                fwrite($worksheetFilePointer, $mergeCellString);
+            }
+
+            // Add the legacy drawing for comments
+            fwrite($worksheetFilePointer, '<legacyDrawing r:id="rId_comments_vml1"/>');
+
+            fwrite($worksheetFilePointer, '</worksheet>');
+            fclose($worksheetFilePointer);
+        }
+
+        return $this;
+    }
+
+    /**
+     * Deletes the temporary folder where sheets content was stored.
+     */
+    public function deleteWorksheetTempFolder(): self
+    {
+        $this->deleteFolderRecursively($this->sheetsContentTempFolder);
+
+        return $this;
+    }
+
     /**
      * Zips the root folder and streams the contents of the zip into the given stream.
      *
      * @param resource $streamPointer Pointer to the stream to copy the zip
      */
-    public function zipRootFolderAndCopyToStream($streamPointer)
+    public function zipRootFolderAndCopyToStream($streamPointer): void
     {
         $zip = $this->zipHelper->createZip($this->rootFolder);
 
@@ -230,8 +398,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
         // to the zip file in a particular order.
         // "[Content_Types].xml" then at least 2 files located in "xl" folder should be zipped first.
         $this->zipHelper->addFileToArchive($zip, $this->rootFolder, self::CONTENT_TYPES_XML_FILE_NAME);
-        $this->zipHelper->addFileToArchive($zip, $this->rootFolder, self::XL_FOLDER_NAME.'/'.self::WORKBOOK_XML_FILE_NAME);
-        $this->zipHelper->addFileToArchive($zip, $this->rootFolder, self::XL_FOLDER_NAME.'/'.self::STYLES_XML_FILE_NAME);
+        $this->zipHelper->addFileToArchive($zip, $this->rootFolder, self::XL_FOLDER_NAME.\DIRECTORY_SEPARATOR.self::WORKBOOK_XML_FILE_NAME);
+        $this->zipHelper->addFileToArchive($zip, $this->rootFolder, self::XL_FOLDER_NAME.\DIRECTORY_SEPARATOR.self::STYLES_XML_FILE_NAME);
 
         $this->zipHelper->addFolderToArchive($zip, $this->rootFolder, ZipHelper::EXISTING_FILES_SKIP);
         $this->zipHelper->closeArchiveAndCopyToStream($zip, $streamPointer);
@@ -240,14 +408,51 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
         $this->deleteFile($zipFilePath);
     }
 
+    /**
+     * Construct column width references xml to inject into worksheet xml file.
+     */
+    private function getXMLFragmentForColumnWidths(Options $options, Sheet $sheet): string
+    {
+        if ([] !== $sheet->getColumnWidths()) {
+            $widths = $sheet->getColumnWidths();
+        } elseif ([] !== $options->getColumnWidths()) {
+            $widths = $options->getColumnWidths();
+        } else {
+            return '';
+        }
+
+        $xml = '<cols>';
+
+        foreach ($widths as $columnWidth) {
+            $xml .= '<col min="'.$columnWidth->start.'" max="'.$columnWidth->end.'" width="'.$columnWidth->width.'" customWidth="true"/>';
+        }
+        $xml .= '</cols>';
+
+        return $xml;
+    }
+
+    /**
+     * Constructs default row height and width xml to inject into worksheet xml file.
+     */
+    private function getXMLFragmentForDefaultCellSizing(Options $options): string
+    {
+        $rowHeightXml = null === $options->DEFAULT_ROW_HEIGHT ? '' : " defaultRowHeight=\"{$options->DEFAULT_ROW_HEIGHT}\"";
+        $colWidthXml = null === $options->DEFAULT_COLUMN_WIDTH ? '' : " defaultColWidth=\"{$options->DEFAULT_COLUMN_WIDTH}\"";
+        if ('' === $colWidthXml && '' === $rowHeightXml) {
+            return '';
+        }
+        // Ensure that the required defaultRowHeight is set
+        $rowHeightXml = '' === $rowHeightXml ? ' defaultRowHeight="0"' : $rowHeightXml;
+
+        return "<sheetFormatPr{$colWidthXml}{$rowHeightXml}/>";
+    }
+
     /**
      * Creates the folder that will be used as root.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder
-     *
-     * @return FileSystemHelper
      */
-    private function createRootFolder()
+    private function createRootFolder(): self
     {
         $this->rootFolder = $this->createFolder($this->baseFolderRealPath, uniqid('xlsx', true));
 
@@ -258,10 +463,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "_rels" folder under the root folder as well as the ".rels" file in it.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder or the ".rels" file
-     *
-     * @return FileSystemHelper
      */
-    private function createRelsFolderAndFile()
+    private function createRelsFolderAndFile(): self
     {
         $this->relsFolder = $this->createFolder($this->rootFolder, self::RELS_FOLDER_NAME);
 
@@ -274,10 +477,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the ".rels" file under the "_rels" folder (under root).
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the file
-     *
-     * @return FileSystemHelper
      */
-    private function createRelsFile()
+    private function createRelsFile(): self
     {
         $relsFileContents = <<<'EOD'
             <?xml version="1.0" encoding="UTF-8"?>
@@ -297,10 +498,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "docProps" folder under the root folder as well as the "app.xml" and "core.xml" files in it.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder or one of the files
-     *
-     * @return FileSystemHelper
      */
-    private function createDocPropsFolderAndFiles()
+    private function createDocPropsFolderAndFiles(): self
     {
         $this->docPropsFolder = $this->createFolder($this->rootFolder, self::DOC_PROPS_FOLDER_NAME);
 
@@ -314,10 +513,8 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "app.xml" file under the "docProps" folder.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the file
-     *
-     * @return FileSystemHelper
      */
-    private function createAppXmlFile()
+    private function createAppXmlFile(): self
     {
         $appName = self::APP_NAME;
         $appXmlFileContents = <<<EOD
@@ -337,12 +534,10 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "core.xml" file under the "docProps" folder.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the file
-     *
-     * @return FileSystemHelper
      */
-    private function createCoreXmlFile()
+    private function createCoreXmlFile(): self
     {
-        $createdDate = (new \DateTime())->format(\DateTime::W3C);
+        $createdDate = (new DateTimeImmutable())->format(DateTimeImmutable::W3C);
         $coreXmlFileContents = <<<EOD
             <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
             <cp:coreProperties xmlns:cp="http://schemas.openxmlformats.org/package/2006/metadata/core-properties" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:dcmitype="http://purl.org/dc/dcmitype/" xmlns:dcterms="http://purl.org/dc/terms/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance">
@@ -361,14 +556,26 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "xl" folder under the root folder as well as its subfolders.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create at least one of the folders
-     *
-     * @return FileSystemHelper
      */
-    private function createXlFolderAndSubFolders()
+    private function createXlFolderAndSubFolders(): self
     {
         $this->xlFolder = $this->createFolder($this->rootFolder, self::XL_FOLDER_NAME);
         $this->createXlRelsFolder();
         $this->createXlWorksheetsFolder();
+        $this->createDrawingsFolder();
+
+        return $this;
+    }
+
+    /**
+     * Creates the temp folder where specific sheets content will be written to.
+     * This folder is not part of the final ODS file and is only used to be able to jump between sheets.
+     *
+     * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder
+     */
+    private function createSheetsContentTempFolder(): self
+    {
+        $this->sheetsContentTempFolder = $this->createFolder($this->rootFolder, 'worksheets-temp');
 
         return $this;
     }
@@ -377,27 +584,51 @@ class FileSystemHelper extends \OpenSpout\Common\Helper\FileSystemHelper impleme
      * Creates the "_rels" folder under the "xl" folder.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder
-     *
-     * @return FileSystemHelper
      */
-    private function createXlRelsFolder()
+    private function createXlRelsFolder(): self
     {
         $this->xlRelsFolder = $this->createFolder($this->xlFolder, self::RELS_FOLDER_NAME);
 
         return $this;
     }
 
+    /**
+     * Creates the "drawings" folder under the "xl" folder.
+     *
+     * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder
+     */
+    private function createDrawingsFolder(): self
+    {
+        $this->createFolder($this->getXlFolder(), self::DRAWINGS_FOLDER_NAME);
+
+        return $this;
+    }
+
     /**
      * Creates the "worksheets" folder under the "xl" folder.
      *
      * @throws \OpenSpout\Common\Exception\IOException If unable to create the folder
-     *
-     * @return FileSystemHelper
      */
-    private function createXlWorksheetsFolder()
+    private function createXlWorksheetsFolder(): self
     {
         $this->xlWorksheetsFolder = $this->createFolder($this->xlFolder, self::WORKSHEETS_FOLDER_NAME);
 
         return $this;
     }
+
+    /**
+     * Streams the content of the file at the given path into the target resource.
+     * Depending on which mode the target resource was created with, it will truncate then copy
+     * or append the content to the target file.
+     *
+     * @param string   $sourceFilePath Path of the file whose content will be copied
+     * @param resource $targetResource Target resource that will receive the content
+     */
+    private function copyFileContentsToTarget(string $sourceFilePath, $targetResource): void
+    {
+        $sourceHandle = fopen($sourceFilePath, 'r');
+        \assert(false !== $sourceHandle);
+        stream_copy_to_stream($sourceHandle, $targetResource);
+        fclose($sourceHandle);
+    }
 }
diff --git a/lib/openspout/src/Writer/XLSX/Manager/CommentsManager.php b/lib/openspout/src/Writer/XLSX/Manager/CommentsManager.php
new file mode 100644
index 00000000000..525289c3782
--- /dev/null
+++ b/lib/openspout/src/Writer/XLSX/Manager/CommentsManager.php
@@ -0,0 +1,225 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Writer\XLSX\Manager;
+
+use OpenSpout\Common\Entity\Comment\Comment;
+use OpenSpout\Common\Entity\Row;
+use OpenSpout\Common\Helper\Escaper;
+use OpenSpout\Writer\Common\Entity\Worksheet;
+use OpenSpout\Writer\Common\Helper\CellHelper;
+
+/**
+ * @internal
+ *
+ * This manager takes care of comments: writing them into two files:
+ *  - commentsX.xml, containing the actual (rich) text of the comment
+ *  - drawings/drawingX.vml, containing the layout of the panel showing the comment
+ *
+ * Each worksheet gets its unique set of 2 files, this class will make sure that these
+ * files are created, closed and filled with the required data.
+ */
+final class CommentsManager
+{
+    public const COMMENTS_XML_FILE_HEADER = <<<'EOD'
+        <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+        <comments xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main">
+            <authors><author>Unknown</author></authors>
+            <commentList>
+        EOD;
+
+    public const COMMENTS_XML_FILE_FOOTER = <<<'EOD'
+            </commentList>
+        </comments>
+        EOD;
+
+    public const DRAWINGS_VML_FILE_HEADER = <<<'EOD'
+        <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+        <xml xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:x="urn:schemas-microsoft-com:office:excel">
+          <o:shapelayout v:ext="edit">
+            <o:idmap v:ext="edit" data="1"/>
+          </o:shapelayout>
+          <v:shapetype id="_x0000_t202" coordsize="21600,21600" o:spt="202" path="m,l,21600r21600,l21600,xe">
+            <v:stroke joinstyle="miter"/>
+            <v:path gradientshapeok="t" o:connecttype="rect"/>
+          </v:shapetype>
+        EOD;
+
+    public const DRAWINGS_VML_FILE_FOOTER = <<<'EOD'
+        </xml>
+        EOD;
+
+    /**
+     * File-pointers to the commentsX.xml files, where the index is the id of the worksheet.
+     *
+     * @var resource[]
+     */
+    private array $commentsFilePointers = [];
+
+    /**
+     * File-pointers to the vmlDrawingX.vml files, where the index is the id of the worksheet.
+     *
+     * @var resource[]
+     */
+    private array $drawingFilePointers = [];
+
+    private string $xlFolder;
+
+    private int $shapeId = 1024;
+
+    private Escaper\XLSX $stringsEscaper;
+
+    /**
+     * @param string $xlFolder Path to the "xl" folder
+     */
+    public function __construct(string $xlFolder, Escaper\XLSX $stringsEscaper)
+    {
+        $this->xlFolder = $xlFolder;
+        $this->stringsEscaper = $stringsEscaper;
+    }
+
+    /**
+     * Create the two comment-files for the given worksheet.
+     */
+    public function createWorksheetCommentFiles(Worksheet $sheet): void
+    {
+        $sheetId = $sheet->getId();
+        $commentFp = fopen($this->getCommentsFilePath($sheet), 'w');
+        \assert(false !== $commentFp);
+
+        $drawingFp = fopen($this->getDrawingFilePath($sheet), 'w');
+        \assert(false !== $drawingFp);
+
+        fwrite($commentFp, self::COMMENTS_XML_FILE_HEADER);
+        fwrite($drawingFp, self::DRAWINGS_VML_FILE_HEADER);
+
+        $this->commentsFilePointers[$sheetId] = $commentFp;
+        $this->drawingFilePointers[$sheetId] = $drawingFp;
+    }
+
+    /**
+     * Close the two comment-files for the given worksheet.
+     */
+    public function closeWorksheetCommentFiles(Worksheet $sheet): void
+    {
+        $sheetId = $sheet->getId();
+
+        $commentFp = $this->commentsFilePointers[$sheetId];
+        $drawingFp = $this->drawingFilePointers[$sheetId];
+
+        fwrite($commentFp, self::COMMENTS_XML_FILE_FOOTER);
+        fwrite($drawingFp, self::DRAWINGS_VML_FILE_FOOTER);
+
+        fclose($commentFp);
+        fclose($drawingFp);
+    }
+
+    public function addComments(Worksheet $worksheet, Row $row): void
+    {
+        $rowIndexZeroBased = 0 + $worksheet->getLastWrittenRowIndex();
+        foreach ($row->getCells() as $columnIndexZeroBased => $cell) {
+            if (null === $cell->comment) {
+                continue;
+            }
+
+            $this->addXmlComment($worksheet->getId(), $rowIndexZeroBased, $columnIndexZeroBased, $cell->comment);
+            $this->addVmlComment($worksheet->getId(), $rowIndexZeroBased, $columnIndexZeroBased, $cell->comment);
+        }
+    }
+
+    /**
+     * @return string The file path where the comments for the given sheet will be stored
+     */
+    private function getCommentsFilePath(Worksheet $sheet): string
+    {
+        return $this->xlFolder.\DIRECTORY_SEPARATOR.'comments'.$sheet->getId().'.xml';
+    }
+
+    /**
+     * @return string The file path where the VML comments for the given sheet will be stored
+     */
+    private function getDrawingFilePath(Worksheet $sheet): string
+    {
+        return $this->xlFolder.\DIRECTORY_SEPARATOR.'drawings'.\DIRECTORY_SEPARATOR.'vmlDrawing'.$sheet->getId().'.vml';
+    }
+
+    /**
+     * Add a comment to the commentsX.xml file.
+     *
+     * @param int     $sheetId              The id of the sheet (starting with 1)
+     * @param int     $rowIndexZeroBased    The row index, starting at 0, of the cell with the comment
+     * @param int     $columnIndexZeroBased The column index, starting at 0, of the cell with the comment
+     * @param Comment $comment              The actual comment
+     */
+    private function addXmlComment(int $sheetId, int $rowIndexZeroBased, int $columnIndexZeroBased, Comment $comment): void
+    {
+        $commentsFilePointer = $this->commentsFilePointers[$sheetId];
+        $rowIndexOneBased = $rowIndexZeroBased + 1;
+        $columnLetters = CellHelper::getColumnLettersFromColumnIndex($columnIndexZeroBased);
+
+        $commentxml = '<comment ref="'.$columnLetters.$rowIndexOneBased.'" authorId="0"><text>';
+        foreach ($comment->getTextRuns() as $line) {
+            $commentxml .= '<r>';
+            $commentxml .= '  <rPr>';
+            if ($line->bold) {
+                $commentxml .= '    <b/>';
+            }
+            if ($line->italic) {
+                $commentxml .= '    <i/>';
+            }
+            $commentxml .= '    <sz val="'.$line->fontSize.'"/>';
+            $commentxml .= '    <color rgb="'.$line->fontColor.'"/>';
+            $commentxml .= '    <rFont val="'.$line->fontName.'"/>';
+            $commentxml .= '    <family val="2"/>';
+            $commentxml .= '  </rPr>';
+            $commentxml .= '  <t xml:space="preserve">'.$this->stringsEscaper->escape($line->text).'</t>';
+            $commentxml .= '</r>';
+        }
+        $commentxml .= '</text></comment>';
+
+        fwrite($commentsFilePointer, $commentxml);
+    }
+
+    /**
+     * Add a comment to the vmlDrawingX.vml file.
+     *
+     * @param int     $sheetId              The id of the sheet (starting with 1)
+     * @param int     $rowIndexZeroBased    The row index, starting at 0, of the cell with the comment
+     * @param int     $columnIndexZeroBased The column index, starting at 0, of the cell with the comment
+     * @param Comment $comment              The actual comment
+     */
+    private function addVmlComment(int $sheetId, int $rowIndexZeroBased, int $columnIndexZeroBased, Comment $comment): void
+    {
+        $drawingFilePointer = $this->drawingFilePointers[$sheetId];
+        ++$this->shapeId;
+
+        $style = 'position:absolute;z-index:1';
+        $style .= ';margin-left:'.$comment->marginLeft;
+        $style .= ';margin-top:'.$comment->marginTop;
+        $style .= ';width:'.$comment->width;
+        $style .= ';height:'.$comment->height;
+        if (!$comment->visible) {
+            $style .= ';visibility:hidden';
+        }
+
+        $drawingVml = '<v:shape id="_x0000_s'.$this->shapeId.'"';
+        $drawingVml .= ' type="#_x0000_t202" style="'.$style.'" fillcolor="'.$comment->fillColor.'" o:insetmode="auto">';
+        $drawingVml .= '<v:fill color2="'.$comment->fillColor.'"/>';
+        $drawingVml .= '<v:shadow on="t" color="black" obscured="t"/>';
+        $drawingVml .= '<v:path o:connecttype="none"/>';
+        $drawingVml .= '<v:textbox style="mso-direction-alt:auto">';
+        $drawingVml .= '  <div style="text-align:left"/>';
+        $drawingVml .= '</v:textbox>';
+        $drawingVml .= '<x:ClientData ObjectType="Note">';
+        $drawingVml .= '  <x:MoveWithCells/>';
+        $drawingVml .= '  <x:SizeWithCells/>';
+        $drawingVml .= '  <x:AutoFill>False</x:AutoFill>';
+        $drawingVml .= '  <x:Row>'.$rowIndexZeroBased.'</x:Row>';
+        $drawingVml .= '  <x:Column>'.$columnIndexZeroBased.'</x:Column>';
+        $drawingVml .= '</x:ClientData>';
+        $drawingVml .= '</v:shape>';
+
+        fwrite($drawingFilePointer, $drawingVml);
+    }
+}
diff --git a/lib/openspout/src/Writer/XLSX/Manager/OptionsManager.php b/lib/openspout/src/Writer/XLSX/Manager/OptionsManager.php
deleted file mode 100644
index b7e7eaebd1f..00000000000
--- a/lib/openspout/src/Writer/XLSX/Manager/OptionsManager.php
+++ /dev/null
@@ -1,64 +0,0 @@
-<?php
-
-namespace OpenSpout\Writer\XLSX\Manager;
-
-use OpenSpout\Common\Manager\OptionsManagerAbstract;
-use OpenSpout\Writer\Common\Creator\Style\StyleBuilder;
-use OpenSpout\Writer\Common\Entity\Options;
-
-/**
- * XLSX Writer options manager.
- */
-class OptionsManager extends OptionsManagerAbstract
-{
-    /** Default style font values */
-    public const DEFAULT_FONT_SIZE = 12;
-    public const DEFAULT_FONT_NAME = 'Calibri';
-
-    /** @var StyleBuilder Style builder */
-    protected $styleBuilder;
-
-    /**
-     * OptionsManager constructor.
-     */
-    public function __construct(StyleBuilder $styleBuilder)
-    {
-        $this->styleBuilder = $styleBuilder;
-        parent::__construct();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function getSupportedOptions()
-    {
-        return [
-            Options::TEMP_FOLDER,
-            Options::DEFAULT_ROW_STYLE,
-            Options::SHOULD_CREATE_NEW_SHEETS_AUTOMATICALLY,
-            Options::SHOULD_USE_INLINE_STRINGS,
-            Options::DEFAULT_COLUMN_WIDTH,
-            Options::DEFAULT_ROW_HEIGHT,
-            Options::COLUMN_WIDTHS,
-            Options::MERGE_CELLS,
-        ];
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    protected function setDefaultOptions()
-    {
-        $defaultRowStyle = $this->styleBuilder
-            ->setFontSize(self::DEFAULT_FONT_SIZE)
-            ->setFontName(self::DEFAULT_FONT_NAME)
-            ->build()
-        ;
-
-        $this->setOption(Options::TEMP_FOLDER, sys_get_temp_dir());
-        $this->setOption(Options::DEFAULT_ROW_STYLE, $defaultRowStyle);
-        $this->setOption(Options::SHOULD_CREATE_NEW_SHEETS_AUTOMATICALLY, true);
-        $this->setOption(Options::SHOULD_USE_INLINE_STRINGS, true);
-        $this->setOption(Options::MERGE_CELLS, []);
-    }
-}
diff --git a/lib/openspout/src/Writer/XLSX/Manager/SharedStringsManager.php b/lib/openspout/src/Writer/XLSX/Manager/SharedStringsManager.php
index 97395561a22..3b232c7b614 100644
--- a/lib/openspout/src/Writer/XLSX/Manager/SharedStringsManager.php
+++ b/lib/openspout/src/Writer/XLSX/Manager/SharedStringsManager.php
@@ -1,14 +1,15 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\XLSX\Manager;
 
-use OpenSpout\Common\Exception\IOException;
 use OpenSpout\Common\Helper\Escaper;
 
 /**
- * This class provides functions to write shared strings.
+ * @internal
  */
-class SharedStringsManager
+final class SharedStringsManager
 {
     public const SHARED_STRINGS_FILE_NAME = 'sharedStrings.xml';
 
@@ -24,24 +25,24 @@ class SharedStringsManager
     public const DEFAULT_STRINGS_COUNT_PART = 'count="9999999999999" uniqueCount="9999999999999"';
 
     /** @var resource Pointer to the sharedStrings.xml file */
-    protected $sharedStringsFilePointer;
+    private $sharedStringsFilePointer;
 
     /** @var int Number of shared strings already written */
-    protected $numSharedStrings = 0;
+    private int $numSharedStrings = 0;
 
     /** @var Escaper\XLSX Strings escaper */
-    protected $stringsEscaper;
+    private Escaper\XLSX $stringsEscaper;
 
     /**
      * @param string       $xlFolder       Path to the "xl" folder
      * @param Escaper\XLSX $stringsEscaper Strings escaper
      */
-    public function __construct($xlFolder, $stringsEscaper)
+    public function __construct(string $xlFolder, Escaper\XLSX $stringsEscaper)
     {
-        $sharedStringsFilePath = $xlFolder.'/'.self::SHARED_STRINGS_FILE_NAME;
-        $this->sharedStringsFilePointer = fopen($sharedStringsFilePath, 'w');
-
-        $this->throwIfSharedStringsFilePointerIsNotAvailable();
+        $sharedStringsFilePath = $xlFolder.\DIRECTORY_SEPARATOR.self::SHARED_STRINGS_FILE_NAME;
+        $resource = fopen($sharedStringsFilePath, 'w');
+        \assert(false !== $resource);
+        $this->sharedStringsFilePointer = $resource;
 
         // the headers is split into different parts so that we can fseek and put in the correct count and uniqueCount later
         $header = self::SHARED_STRINGS_XML_FILE_FIRST_PART_HEADER.' '.self::DEFAULT_STRINGS_COUNT_PART.'>';
@@ -54,11 +55,9 @@ class SharedStringsManager
      * Writes the given string into the sharedStrings.xml file.
      * Starting and ending whitespaces are preserved.
      *
-     * @param string $string
-     *
      * @return int ID of the written shared string
      */
-    public function writeString($string)
+    public function writeString(string $string): int
     {
         fwrite($this->sharedStringsFilePointer, '<si><t xml:space="preserve">'.$this->stringsEscaper->escape($string).'</t></si>');
         ++$this->numSharedStrings;
@@ -70,12 +69,8 @@ class SharedStringsManager
     /**
      * Finishes writing the data in the sharedStrings.xml file and closes the file.
      */
-    public function close()
+    public function close(): void
     {
-        if (!\is_resource($this->sharedStringsFilePointer)) {
-            return;
-        }
-
         fwrite($this->sharedStringsFilePointer, '</sst>');
 
         // Replace the default strings count with the actual number of shared strings in the file header
@@ -88,16 +83,4 @@ class SharedStringsManager
 
         fclose($this->sharedStringsFilePointer);
     }
-
-    /**
-     * Checks if the book has been created. Throws an exception if not created yet.
-     *
-     * @throws \OpenSpout\Common\Exception\IOException If the sheet data file cannot be opened for writing
-     */
-    protected function throwIfSharedStringsFilePointerIsNotAvailable()
-    {
-        if (!\is_resource($this->sharedStringsFilePointer)) {
-            throw new IOException('Unable to open shared strings file for writing.');
-        }
-    }
 }
diff --git a/lib/openspout/src/Writer/XLSX/Manager/Style/StyleManager.php b/lib/openspout/src/Writer/XLSX/Manager/Style/StyleManager.php
index 5f284b9511d..3953f4dc5f8 100644
--- a/lib/openspout/src/Writer/XLSX/Manager/Style/StyleManager.php
+++ b/lib/openspout/src/Writer/XLSX/Manager/Style/StyleManager.php
@@ -1,19 +1,26 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\XLSX\Manager\Style;
 
 use OpenSpout\Common\Entity\Style\BorderPart;
 use OpenSpout\Common\Entity\Style\Color;
 use OpenSpout\Common\Entity\Style\Style;
+use OpenSpout\Writer\Common\Manager\Style\AbstractStyleManager as CommonStyleManager;
 use OpenSpout\Writer\XLSX\Helper\BorderHelper;
 
 /**
- * Manages styles to be applied to a cell.
+ * @internal
+ *
+ * @property StyleRegistry $styleRegistry
  */
-class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
+final class StyleManager extends CommonStyleManager
 {
-    /** @var StyleRegistry */
-    protected $styleRegistry;
+    public function __construct(StyleRegistry $styleRegistry)
+    {
+        parent::__construct($styleRegistry);
+    }
 
     /**
      * For empty cells, we can specify a style or not. If no style are specified,
@@ -22,12 +29,13 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
      * background color different than the default one or some borders
      * (fonts property don't really matter here).
      *
-     * @param int $styleId
-     *
      * @return bool Whether the cell should define a custom style
      */
-    public function shouldApplyStyleOnEmptyCell($styleId)
+    public function shouldApplyStyleOnEmptyCell(?int $styleId): bool
     {
+        if (null === $styleId) {
+            return false;
+        }
         $associatedFillId = $this->styleRegistry->getFillIdForStyleId($styleId);
         $hasStyleCustomFill = (null !== $associatedFillId && 0 !== $associatedFillId);
 
@@ -42,10 +50,8 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the content of the "styles.xml" file, given a list of styles.
-     *
-     * @return string
      */
-    public function getStylesXMLFileContent()
+    public function getStylesXMLFileContent(): string
     {
         $content = <<<'EOD'
             <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
@@ -69,17 +75,15 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the content of the "<numFmts>" section.
-     *
-     * @return string
      */
-    protected function getFormatsSectionContent()
+    private function getFormatsSectionContent(): string
     {
         $tags = [];
         $registeredFormats = $this->styleRegistry->getRegisteredFormats();
         foreach ($registeredFormats as $styleId) {
             $numFmtId = $this->styleRegistry->getFormatIdForStyleId($styleId);
 
-            //Built-in formats do not need to be declared, skip them
+            // Built-in formats do not need to be declared, skip them
             if ($numFmtId < 164) {
                 continue;
             }
@@ -98,10 +102,8 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the content of the "<fonts>" section.
-     *
-     * @return string
      */
-    protected function getFontsSectionContent()
+    private function getFontsSectionContent(): string
     {
         $registeredStyles = $this->styleRegistry->getRegisteredStyles();
 
@@ -138,10 +140,8 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the content of the "<fills>" section.
-     *
-     * @return string
      */
-    protected function getFillsSectionContent()
+    private function getFillsSectionContent(): string
     {
         $registeredFills = $this->styleRegistry->getRegisteredFills();
 
@@ -171,10 +171,8 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the content of the "<borders>" section.
-     *
-     * @return string
      */
-    protected function getBordersSectionContent()
+    private function getBordersSectionContent(): string
     {
         $registeredBorders = $this->styleRegistry->getRegisteredBorders();
 
@@ -187,20 +185,14 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
         $content .= '<border><left/><right/><top/><bottom/></border>';
 
         foreach ($registeredBorders as $styleId) {
-            /** @var Style $style */
             $style = $this->styleRegistry->getStyleFromStyleId($styleId);
             $border = $style->getBorder();
+            \assert(null !== $border);
             $content .= '<border>';
 
-            /** @see https://github.com/box/spout/issues/271 */
-            $sortOrder = ['left', 'right', 'top', 'bottom'];
-
-            foreach ($sortOrder as $partName) {
-                if ($border->hasPart($partName)) {
-                    /** @var BorderPart $part */
-                    $part = $border->getPart($partName);
-                    $content .= BorderHelper::serializeBorderPart($part);
-                }
+            // @see https://github.com/box/spout/issues/271
+            foreach (BorderPart::allowedNames as $partName) {
+                $content .= BorderHelper::serializeBorderPart($border->getPart($partName));
             }
 
             $content .= '</border>';
@@ -213,10 +205,8 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the content of the "<cellStyleXfs>" section.
-     *
-     * @return string
      */
-    protected function getCellStyleXfsSectionContent()
+    private function getCellStyleXfsSectionContent(): string
     {
         return <<<'EOD'
             <cellStyleXfs count="1">
@@ -227,10 +217,8 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the content of the "<cellXfs>" section.
-     *
-     * @return string
      */
-    protected function getCellXfsSectionContent()
+    private function getCellXfsSectionContent(): string
     {
         $registeredStyles = $this->styleRegistry->getRegisteredStyles();
 
@@ -248,16 +236,19 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
                 $content .= ' applyFont="1"';
             }
 
-            $content .= sprintf(' applyBorder="%d"', $style->shouldApplyBorder() ? 1 : 0);
+            $content .= sprintf(' applyBorder="%d"', (bool) $style->getBorder());
 
-            if ($style->shouldApplyCellAlignment() || $style->shouldWrapText() || $style->shouldShrinkToFit()) {
+            if ($style->shouldApplyCellAlignment() || $style->shouldApplyCellVerticalAlignment() || $style->hasSetWrapText() || $style->shouldShrinkToFit()) {
                 $content .= ' applyAlignment="1">';
                 $content .= '<alignment';
                 if ($style->shouldApplyCellAlignment()) {
                     $content .= sprintf(' horizontal="%s"', $style->getCellAlignment());
                 }
-                if ($style->shouldWrapText()) {
-                    $content .= ' wrapText="1"';
+                if ($style->shouldApplyCellVerticalAlignment()) {
+                    $content .= sprintf(' vertical="%s"', $style->getCellVerticalAlignment());
+                }
+                if ($style->hasSetWrapText()) {
+                    $content .= ' wrapText="'.($style->shouldWrapText() ? '1' : '0').'"';
                 }
                 if ($style->shouldShrinkToFit()) {
                     $content .= ' shrinkToFit="true"';
@@ -277,10 +268,8 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
 
     /**
      * Returns the content of the "<cellStyles>" section.
-     *
-     * @return string
      */
-    protected function getCellStylesSectionContent()
+    private function getCellStylesSectionContent(): string
     {
         return <<<'EOD'
             <cellStyles count="1">
@@ -292,51 +281,39 @@ class StyleManager extends \OpenSpout\Writer\Common\Manager\Style\StyleManager
     /**
      * Returns the fill ID associated to the given style ID.
      * For the default style, we don't a fill.
-     *
-     * @param int $styleId
-     *
-     * @return int
      */
-    private function getFillIdForStyleId($styleId)
+    private function getFillIdForStyleId(int $styleId): int
     {
         // For the default style (ID = 0), we don't want to override the fill.
         // Otherwise all cells of the spreadsheet will have a background color.
         $isDefaultStyle = (0 === $styleId);
 
-        return $isDefaultStyle ? 0 : ($this->styleRegistry->getFillIdForStyleId($styleId) ?: 0);
+        return $isDefaultStyle ? 0 : ($this->styleRegistry->getFillIdForStyleId($styleId) ?? 0);
     }
 
     /**
      * Returns the fill ID associated to the given style ID.
      * For the default style, we don't a border.
-     *
-     * @param int $styleId
-     *
-     * @return int
      */
-    private function getBorderIdForStyleId($styleId)
+    private function getBorderIdForStyleId(int $styleId): int
     {
         // For the default style (ID = 0), we don't want to override the border.
         // Otherwise all cells of the spreadsheet will have a border.
         $isDefaultStyle = (0 === $styleId);
 
-        return $isDefaultStyle ? 0 : ($this->styleRegistry->getBorderIdForStyleId($styleId) ?: 0);
+        return $isDefaultStyle ? 0 : ($this->styleRegistry->getBorderIdForStyleId($styleId) ?? 0);
     }
 
     /**
      * Returns the format ID associated to the given style ID.
      * For the default style use general format.
-     *
-     * @param int $styleId
-     *
-     * @return int
      */
-    private function getFormatIdForStyleId($styleId)
+    private function getFormatIdForStyleId(int $styleId): int
     {
         // For the default style (ID = 0), we don't want to override the format.
         // Otherwise all cells of the spreadsheet will have a format.
         $isDefaultStyle = (0 === $styleId);
 
-        return $isDefaultStyle ? 0 : ($this->styleRegistry->getFormatIdForStyleId($styleId) ?: 0);
+        return $isDefaultStyle ? 0 : ($this->styleRegistry->getFormatIdForStyleId($styleId) ?? 0);
     }
 }
diff --git a/lib/openspout/src/Writer/XLSX/Manager/Style/StyleRegistry.php b/lib/openspout/src/Writer/XLSX/Manager/Style/StyleRegistry.php
index 259d4e8408d..374638d1117 100644
--- a/lib/openspout/src/Writer/XLSX/Manager/Style/StyleRegistry.php
+++ b/lib/openspout/src/Writer/XLSX/Manager/Style/StyleRegistry.php
@@ -1,20 +1,23 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\XLSX\Manager\Style;
 
 use OpenSpout\Common\Entity\Style\Style;
+use OpenSpout\Writer\Common\Manager\Style\AbstractStyleRegistry as CommonStyleRegistry;
 
 /**
- * Registry for all used styles.
+ * @internal
  */
-class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
+class StyleRegistry extends CommonStyleRegistry
 {
     /**
-     * @see https://msdn.microsoft.com/en-us/library/ff529597(v=office.12).aspx
+     * Mapping between built-in format and the associated numFmtId.
      *
-     * @var array Mapping between built-in format and the associated numFmtId
+     * @see https://msdn.microsoft.com/en-us/library/ff529597(v=office.12).aspx
      */
-    protected static $builtinNumFormatToIdMapping = [
+    private const builtinNumFormatToIdMapping = [
         'General' => 0,
         '0' => 1,
         '0.00' => 2,
@@ -64,15 +67,11 @@ class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
         't# ??/??' => 70,
     ];
 
-    /**
-     * @var array
-     */
-    protected $registeredFormats = [];
+    /** @var array<string, int> */
+    private array $registeredFormats = [];
 
-    /**
-     * @var array [STYLE_ID] => [FORMAT_ID] maps a style to a format declaration
-     */
-    protected $styleIdToFormatsMappingTable = [];
+    /** @var array<int, int> [STYLE_ID] => [FORMAT_ID] maps a style to a format declaration */
+    private array $styleIdToFormatsMappingTable = [];
 
     /**
      * If the numFmtId is lower than 0xA4 (164 in decimal)
@@ -81,17 +80,13 @@ class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
      *
      * @var int the fill index counter for custom fills
      */
-    protected $formatIndex = 164;
+    private int $formatIndex = 164;
 
-    /**
-     * @var array
-     */
-    protected $registeredFills = [];
+    /** @var array<string, int> */
+    private array $registeredFills = [];
 
-    /**
-     * @var array [STYLE_ID] => [FILL_ID] maps a style to a fill declaration
-     */
-    protected $styleIdToFillMappingTable = [];
+    /** @var array<int, int> [STYLE_ID] => [FILL_ID] maps a style to a fill declaration */
+    private array $styleIdToFillMappingTable = [];
 
     /**
      * Excel preserves two default fills with index 0 and 1
@@ -99,24 +94,18 @@ class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
      *
      * @var int the fill index counter for custom fills
      */
-    protected $fillIndex = 2;
+    private int $fillIndex = 2;
 
-    /**
-     * @var array
-     */
-    protected $registeredBorders = [];
+    /** @var array<string, int> */
+    private array $registeredBorders = [];
 
-    /**
-     * @var array [STYLE_ID] => [BORDER_ID] maps a style to a border declaration
-     */
-    protected $styleIdToBorderMappingTable = [];
+    /** @var array<int, int> [STYLE_ID] => [BORDER_ID] maps a style to a border declaration */
+    private array $styleIdToBorderMappingTable = [];
 
     /**
      * XLSX specific operations on the registered styles.
-     *
-     * @return Style
      */
-    public function registerStyle(Style $style)
+    public function registerStyle(Style $style): Style
     {
         if ($style->isRegistered()) {
             return $style;
@@ -131,59 +120,49 @@ class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
     }
 
     /**
-     * @param int $styleId
-     *
      * @return null|int Format ID associated to the given style ID
      */
-    public function getFormatIdForStyleId($styleId)
+    public function getFormatIdForStyleId(int $styleId): ?int
     {
         return $this->styleIdToFormatsMappingTable[$styleId] ?? null;
     }
 
     /**
-     * @param int $styleId
-     *
      * @return null|int Fill ID associated to the given style ID
      */
-    public function getFillIdForStyleId($styleId)
+    public function getFillIdForStyleId(int $styleId): ?int
     {
-        return (isset($this->styleIdToFillMappingTable[$styleId])) ?
-            $this->styleIdToFillMappingTable[$styleId] :
-            null;
+        return $this->styleIdToFillMappingTable[$styleId] ?? null;
     }
 
     /**
-     * @param int $styleId
-     *
      * @return null|int Fill ID associated to the given style ID
      */
-    public function getBorderIdForStyleId($styleId)
+    public function getBorderIdForStyleId(int $styleId): ?int
     {
-        return (isset($this->styleIdToBorderMappingTable[$styleId])) ?
-            $this->styleIdToBorderMappingTable[$styleId] :
-            null;
+        return $this->styleIdToBorderMappingTable[$styleId] ?? null;
     }
 
     /**
-     * @return array
+     * @return array<string, int>
      */
-    public function getRegisteredFills()
+    public function getRegisteredFills(): array
     {
         return $this->registeredFills;
     }
 
     /**
-     * @return array
+     * @return array<string, int>
      */
-    public function getRegisteredBorders()
+    public function getRegisteredBorders(): array
     {
         return $this->registeredBorders;
     }
 
     /**
-     * @return array
+     * @return array<string, int>
      */
-    public function getRegisteredFormats()
+    public function getRegisteredFormats(): array
     {
         return $this->registeredFormats;
     }
@@ -191,12 +170,12 @@ class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
     /**
      * Register a format definition.
      */
-    protected function registerFormat(Style $style)
+    private function registerFormat(Style $style): void
     {
         $styleId = $style->getId();
 
         $format = $style->getFormat();
-        if ($format) {
+        if (null !== $format) {
             $isFormatRegistered = isset($this->registeredFormats[$format]);
 
             // We need to track the already registered format definitions
@@ -207,7 +186,7 @@ class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
             } else {
                 $this->registeredFormats[$format] = $styleId;
 
-                $id = self::$builtinNumFormatToIdMapping[$format] ?? $this->formatIndex++;
+                $id = self::builtinNumFormatToIdMapping[$format] ?? $this->formatIndex++;
                 $this->styleIdToFormatsMappingTable[$styleId] = $id;
             }
         } else {
@@ -220,7 +199,7 @@ class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
     /**
      * Register a fill definition.
      */
-    private function registerFill(Style $style)
+    private function registerFill(Style $style): void
     {
         $styleId = $style->getId();
 
@@ -228,7 +207,7 @@ class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
         // so $backgroundColor is a scalar value (RGB Color)
         $backgroundColor = $style->getBackgroundColor();
 
-        if ($backgroundColor) {
+        if (null !== $backgroundColor) {
             $isBackgroundColorRegistered = isset($this->registeredFills[$backgroundColor]);
 
             // We need to track the already registered background definitions
@@ -250,12 +229,11 @@ class StyleRegistry extends \OpenSpout\Writer\Common\Manager\Style\StyleRegistry
     /**
      * Register a border definition.
      */
-    private function registerBorder(Style $style)
+    private function registerBorder(Style $style): void
     {
         $styleId = $style->getId();
 
-        if ($style->shouldApplyBorder()) {
-            $border = $style->getBorder();
+        if (null !== ($border = $style->getBorder())) {
             $serializedBorder = serialize($border);
 
             $isBorderAlreadyRegistered = isset($this->registeredBorders[$serializedBorder]);
diff --git a/lib/openspout/src/Writer/XLSX/Manager/WorkbookManager.php b/lib/openspout/src/Writer/XLSX/Manager/WorkbookManager.php
index 2feb331d86c..8404c47041f 100644
--- a/lib/openspout/src/Writer/XLSX/Manager/WorkbookManager.php
+++ b/lib/openspout/src/Writer/XLSX/Manager/WorkbookManager.php
@@ -1,47 +1,56 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\XLSX\Manager;
 
 use OpenSpout\Writer\Common\Entity\Sheet;
-use OpenSpout\Writer\Common\Manager\WorkbookManagerAbstract;
+use OpenSpout\Writer\Common\Entity\Workbook;
+use OpenSpout\Writer\Common\Manager\AbstractWorkbookManager;
+use OpenSpout\Writer\Common\Manager\Style\StyleMerger;
 use OpenSpout\Writer\XLSX\Helper\FileSystemHelper;
 use OpenSpout\Writer\XLSX\Manager\Style\StyleManager;
+use OpenSpout\Writer\XLSX\Options;
 
 /**
- * XLSX workbook manager, providing the interfaces to work with workbook.
+ * @internal
+ *
+ * @property WorksheetManager $worksheetManager
+ * @property StyleManager     $styleManager
+ * @property FileSystemHelper $fileSystemHelper
+ * @property Options          $options
  */
-class WorkbookManager extends WorkbookManagerAbstract
+final class WorkbookManager extends AbstractWorkbookManager
 {
     /**
      * Maximum number of rows a XLSX sheet can contain.
      *
      * @see http://office.microsoft.com/en-us/excel-help/excel-specifications-and-limits-HP010073849.aspx
      */
-    protected static $maxRowsPerWorksheet = 1048576;
+    private static int $maxRowsPerWorksheet = 1048576;
 
-    /** @var WorksheetManager Object used to manage worksheets */
-    protected $worksheetManager;
-
-    /** @var StyleManager Manages styles */
-    protected $styleManager;
-
-    /** @var FileSystemHelper Helper to perform file system operations */
-    protected $fileSystemHelper;
-
-    /**
-     * @return string The file path where the data for the given sheet will be stored
-     */
-    public function getWorksheetFilePath(Sheet $sheet)
-    {
-        $worksheetFilesFolder = $this->fileSystemHelper->getXlWorksheetsFolder();
-
-        return $worksheetFilesFolder.'/'.strtolower($sheet->getName()).'.xml';
+    public function __construct(
+        Workbook $workbook,
+        Options $options,
+        WorksheetManager $worksheetManager,
+        StyleManager $styleManager,
+        StyleMerger $styleMerger,
+        FileSystemHelper $fileSystemHelper
+    ) {
+        parent::__construct(
+            $workbook,
+            $options,
+            $worksheetManager,
+            $styleManager,
+            $styleMerger,
+            $fileSystemHelper
+        );
     }
 
     /**
      * @return int Maximum number of rows/columns a sheet can contain
      */
-    protected function getMaxRowsPerWorksheet()
+    protected function getMaxRowsPerWorksheet(): int
     {
         return self::$maxRowsPerWorksheet;
     }
@@ -49,7 +58,7 @@ class WorkbookManager extends WorkbookManagerAbstract
     /**
      * Closes custom objects that are still opened.
      */
-    protected function closeRemainingObjects()
+    protected function closeRemainingObjects(): void
     {
         $this->worksheetManager->getSharedStringsManager()->close();
     }
@@ -59,14 +68,17 @@ class WorkbookManager extends WorkbookManagerAbstract
      *
      * @param resource $finalFilePointer Pointer to the spreadsheet that will be created
      */
-    protected function writeAllFilesToDiskAndZipThem($finalFilePointer)
+    protected function writeAllFilesToDiskAndZipThem($finalFilePointer): void
     {
         $worksheets = $this->getWorksheets();
 
         $this->fileSystemHelper
+            ->createContentFiles($this->options, $worksheets)
+            ->deleteWorksheetTempFolder()
             ->createContentTypesFile($worksheets)
             ->createWorkbookFile($worksheets)
             ->createWorkbookRelsFile($worksheets)
+            ->createWorksheetRelsFiles($worksheets)
             ->createStylesFile($this->styleManager)
             ->zipRootFolderAndCopyToStream($finalFilePointer)
         ;
diff --git a/lib/openspout/src/Writer/XLSX/Manager/WorksheetManager.php b/lib/openspout/src/Writer/XLSX/Manager/WorksheetManager.php
index c84be5ab555..e0e448a29f5 100644
--- a/lib/openspout/src/Writer/XLSX/Manager/WorksheetManager.php
+++ b/lib/openspout/src/Writer/XLSX/Manager/WorksheetManager.php
@@ -1,5 +1,7 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\XLSX\Manager;
 
 use OpenSpout\Common\Entity\Cell;
@@ -9,25 +11,20 @@ use OpenSpout\Common\Exception\InvalidArgumentException;
 use OpenSpout\Common\Exception\IOException;
 use OpenSpout\Common\Helper\Escaper\XLSX as XLSXEscaper;
 use OpenSpout\Common\Helper\StringHelper;
-use OpenSpout\Common\Manager\OptionsManagerInterface;
-use OpenSpout\Writer\Common\Entity\Options;
 use OpenSpout\Writer\Common\Entity\Worksheet;
 use OpenSpout\Writer\Common\Helper\CellHelper;
-use OpenSpout\Writer\Common\Manager\ManagesCellSize;
 use OpenSpout\Writer\Common\Manager\RegisteredStyle;
-use OpenSpout\Writer\Common\Manager\RowManager;
 use OpenSpout\Writer\Common\Manager\Style\StyleMerger;
 use OpenSpout\Writer\Common\Manager\WorksheetManagerInterface;
 use OpenSpout\Writer\XLSX\Helper\DateHelper;
 use OpenSpout\Writer\XLSX\Manager\Style\StyleManager;
+use OpenSpout\Writer\XLSX\Options;
 
 /**
- * XLSX worksheet manager, providing the interfaces to work with XLSX worksheets.
+ * @internal
  */
-class WorksheetManager implements WorksheetManagerInterface
+final class WorksheetManager implements WorksheetManagerInterface
 {
-    use ManagesCellSize;
-
     /**
      * Maximum number of characters a cell can contain.
      *
@@ -37,64 +34,48 @@ class WorksheetManager implements WorksheetManagerInterface
      */
     public const MAX_CHARACTERS_PER_CELL = 32767;
 
-    public const SHEET_XML_FILE_HEADER = <<<'EOD'
-        <?xml version="1.0" encoding="UTF-8" standalone="yes"?>
-        <worksheet xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main" xmlns:r="http://schemas.openxmlformats.org/officeDocument/2006/relationships">
-        EOD;
+    /** @var CommentsManager Manages comments */
+    private CommentsManager $commentsManager;
 
-    /** @var bool Whether inline or shared strings should be used */
-    protected $shouldUseInlineStrings;
-
-    /** @var OptionsManagerInterface */
-    private $optionsManager;
-
-    /** @var RowManager Manages rows */
-    private $rowManager;
+    private Options $options;
 
     /** @var StyleManager Manages styles */
-    private $styleManager;
+    private StyleManager $styleManager;
 
     /** @var StyleMerger Helper to merge styles together */
-    private $styleMerger;
+    private StyleMerger $styleMerger;
 
     /** @var SharedStringsManager Helper to write shared strings */
-    private $sharedStringsManager;
+    private SharedStringsManager $sharedStringsManager;
 
     /** @var XLSXEscaper Strings escaper */
-    private $stringsEscaper;
+    private XLSXEscaper $stringsEscaper;
 
     /** @var StringHelper String helper */
-    private $stringHelper;
+    private StringHelper $stringHelper;
 
     /**
      * WorksheetManager constructor.
      */
     public function __construct(
-        OptionsManagerInterface $optionsManager,
-        RowManager $rowManager,
+        Options $options,
         StyleManager $styleManager,
         StyleMerger $styleMerger,
+        CommentsManager $commentsManager,
         SharedStringsManager $sharedStringsManager,
         XLSXEscaper $stringsEscaper,
         StringHelper $stringHelper
     ) {
-        $this->optionsManager = $optionsManager;
-        $this->shouldUseInlineStrings = $optionsManager->getOption(Options::SHOULD_USE_INLINE_STRINGS);
-        $this->setDefaultColumnWidth($optionsManager->getOption(Options::DEFAULT_COLUMN_WIDTH));
-        $this->setDefaultRowHeight($optionsManager->getOption(Options::DEFAULT_ROW_HEIGHT));
-        $this->columnWidths = $optionsManager->getOption(Options::COLUMN_WIDTHS) ?? [];
-        $this->rowManager = $rowManager;
+        $this->options = $options;
         $this->styleManager = $styleManager;
         $this->styleMerger = $styleMerger;
+        $this->commentsManager = $commentsManager;
         $this->sharedStringsManager = $sharedStringsManager;
         $this->stringsEscaper = $stringsEscaper;
         $this->stringHelper = $stringHelper;
     }
 
-    /**
-     * @return SharedStringsManager
-     */
-    public function getSharedStringsManager()
+    public function getSharedStringsManager(): SharedStringsManager
     {
         return $this->sharedStringsManager;
     }
@@ -102,127 +83,35 @@ class WorksheetManager implements WorksheetManagerInterface
     /**
      * {@inheritdoc}
      */
-    public function startSheet(Worksheet $worksheet)
+    public function startSheet(Worksheet $worksheet): void
     {
         $sheetFilePointer = fopen($worksheet->getFilePath(), 'w');
-        $this->throwIfSheetFilePointerIsNotAvailable($sheetFilePointer);
+        \assert(false !== $sheetFilePointer);
 
         $worksheet->setFilePointer($sheetFilePointer);
-
-        fwrite($sheetFilePointer, self::SHEET_XML_FILE_HEADER);
+        $this->commentsManager->createWorksheetCommentFiles($worksheet);
     }
 
     /**
      * {@inheritdoc}
      */
-    public function addRow(Worksheet $worksheet, Row $row)
+    public function addRow(Worksheet $worksheet, Row $row): void
     {
-        if (!$this->rowManager->isEmpty($row)) {
+        if (!$row->isEmpty()) {
             $this->addNonEmptyRow($worksheet, $row);
+            $this->commentsManager->addComments($worksheet, $row);
         }
 
         $worksheet->setLastWrittenRowIndex($worksheet->getLastWrittenRowIndex() + 1);
     }
 
-    /**
-     * Construct column width references xml to inject into worksheet xml file.
-     *
-     * @return string
-     */
-    public function getXMLFragmentForColumnWidths()
-    {
-        if (empty($this->columnWidths)) {
-            return '';
-        }
-        $xml = '<cols>';
-        foreach ($this->columnWidths as $entry) {
-            $xml .= '<col min="'.$entry[0].'" max="'.$entry[1].'" width="'.$entry[2].'" customWidth="true"/>';
-        }
-        $xml .= '</cols>';
-
-        return $xml;
-    }
-
-    /**
-     * Constructs default row height and width xml to inject into worksheet xml file.
-     *
-     * @return string
-     */
-    public function getXMLFragmentForDefaultCellSizing()
-    {
-        $rowHeightXml = empty($this->defaultRowHeight) ? '' : " defaultRowHeight=\"{$this->defaultRowHeight}\"";
-        $colWidthXml = empty($this->defaultColumnWidth) ? '' : " defaultColWidth=\"{$this->defaultColumnWidth}\"";
-        if (empty($colWidthXml) && empty($rowHeightXml)) {
-            return '';
-        }
-        // Ensure that the required defaultRowHeight is set
-        $rowHeightXml = empty($rowHeightXml) ? ' defaultRowHeight="0"' : $rowHeightXml;
-
-        return "<sheetFormatPr{$colWidthXml}{$rowHeightXml}/>";
-    }
-
     /**
      * {@inheritdoc}
      */
-    public function close(Worksheet $worksheet)
+    public function close(Worksheet $worksheet): void
     {
-        $worksheetFilePointer = $worksheet->getFilePointer();
-
-        if (!\is_resource($worksheetFilePointer)) {
-            return;
-        }
-        $this->ensureSheetDataStated($worksheet);
-        fwrite($worksheetFilePointer, '</sheetData>');
-
-        // create nodes for merge cells
-        if ($this->optionsManager->getOption(Options::MERGE_CELLS)) {
-            $mergeCellString = '<mergeCells count="'.\count($this->optionsManager->getOption(Options::MERGE_CELLS)).'">';
-            foreach ($this->optionsManager->getOption(Options::MERGE_CELLS) as $values) {
-                $output = array_map(function ($value) {
-                    return CellHelper::getColumnLettersFromColumnIndex($value[0]).$value[1];
-                }, $values);
-                $mergeCellString .= '<mergeCell ref="'.implode(':', $output).'"/>';
-            }
-            $mergeCellString .= '</mergeCells>';
-            fwrite($worksheet->getFilePointer(), $mergeCellString);
-        }
-
-        fwrite($worksheetFilePointer, '</worksheet>');
-        fclose($worksheetFilePointer);
-    }
-
-    /**
-     * Writes the sheet data header.
-     *
-     * @param Worksheet $worksheet The worksheet to add the row to
-     */
-    private function ensureSheetDataStated(Worksheet $worksheet)
-    {
-        if (!$worksheet->getSheetDataStarted()) {
-            $worksheetFilePointer = $worksheet->getFilePointer();
-            $sheet = $worksheet->getExternalSheet();
-            if ($sheet->hasSheetView()) {
-                fwrite($worksheetFilePointer, '<sheetViews>'.$sheet->getSheetView()->getXml().'</sheetViews>');
-            }
-            fwrite($worksheetFilePointer, $this->getXMLFragmentForDefaultCellSizing());
-            fwrite($worksheetFilePointer, $this->getXMLFragmentForColumnWidths());
-            fwrite($worksheetFilePointer, '<sheetData>');
-            $worksheet->setSheetDataStarted(true);
-        }
-    }
-
-    /**
-     * Checks if the sheet has been sucessfully created. Throws an exception if not.
-     *
-     * @param bool|resource $sheetFilePointer Pointer to the sheet data file or FALSE if unable to open the file
-     *
-     * @throws IOException If the sheet data file cannot be opened for writing
-     */
-    private function throwIfSheetFilePointerIsNotAvailable($sheetFilePointer)
-    {
-        if (!$sheetFilePointer) {
-            throw new IOException('Unable to open sheet for writing.');
-        }
+        $this->commentsManager->closeWorksheetCommentFiles($worksheet);
+        fclose($worksheet->getFilePointer());
     }
 
     /**
@@ -234,16 +123,16 @@ class WorksheetManager implements WorksheetManagerInterface
      * @throws InvalidArgumentException If a cell value's type is not supported
      * @throws IOException              If the data cannot be written
      */
-    private function addNonEmptyRow(Worksheet $worksheet, Row $row)
+    private function addNonEmptyRow(Worksheet $worksheet, Row $row): void
     {
-        $this->ensureSheetDataStated($worksheet);
         $sheetFilePointer = $worksheet->getFilePointer();
         $rowStyle = $row->getStyle();
         $rowIndexOneBased = $worksheet->getLastWrittenRowIndex() + 1;
         $numCells = $row->getNumCells();
 
-        $hasCustomHeight = $this->defaultRowHeight > 0 ? '1' : '0';
-        $rowXML = "<row r=\"{$rowIndexOneBased}\" spans=\"1:{$numCells}\" customHeight=\"{$hasCustomHeight}\">";
+        $rowHeight = $row->getHeight();
+        $hasCustomHeight = ($this->options->DEFAULT_ROW_HEIGHT > 0 || $rowHeight > 0) ? '1' : '0';
+        $rowXML = "<row r=\"{$rowIndexOneBased}\" spans=\"1:{$numCells}\" ".($rowHeight > 0 ? "ht=\"{$rowHeight}\" " : '')."customHeight=\"{$hasCustomHeight}\">";
 
         foreach ($row->getCells() as $columnIndexZeroBased => $cell) {
             $registeredStyle = $this->applyStyleAndRegister($cell, $rowStyle);
@@ -302,39 +191,28 @@ class WorksheetManager implements WorksheetManagerInterface
     /**
      * Builds and returns xml for a single cell.
      *
-     * @param int $rowIndexOneBased
-     * @param int $columnIndexZeroBased
-     * @param int $styleId
-     *
      * @throws InvalidArgumentException If the given value cannot be processed
-     *
-     * @return string
      */
-    private function getCellXML($rowIndexOneBased, $columnIndexZeroBased, Cell $cell, $styleId)
+    private function getCellXML(int $rowIndexOneBased, int $columnIndexZeroBased, Cell $cell, ?int $styleId): string
     {
         $columnLetters = CellHelper::getColumnLettersFromColumnIndex($columnIndexZeroBased);
         $cellXML = '<c r="'.$columnLetters.$rowIndexOneBased.'"';
         $cellXML .= ' s="'.$styleId.'"';
 
-        if ($cell->isString()) {
+        if ($cell instanceof Cell\StringCell) {
             $cellXML .= $this->getCellXMLFragmentForNonEmptyString($cell->getValue());
-        } elseif ($cell->isBoolean()) {
-            $cellXML .= ' t="b"><v>'.(int) ($cell->getValue()).'</v></c>';
-        } elseif ($cell->isNumeric()) {
-            $cellXML .= '><v>'.$this->stringHelper->formatNumericValue($cell->getValue()).'</v></c>';
-        } elseif ($cell->isFormula()) {
+        } elseif ($cell instanceof Cell\BooleanCell) {
+            $cellXML .= ' t="b"><v>'.(int) $cell->getValue().'</v></c>';
+        } elseif ($cell instanceof Cell\NumericCell) {
+            $cellXML .= '><v>'.$cell->getValue().'</v></c>';
+        } elseif ($cell instanceof Cell\FormulaCell) {
             $cellXML .= '><f>'.substr($cell->getValue(), 1).'</f></c>';
-        } elseif ($cell->isDate()) {
-            $value = $cell->getValue();
-            if ($value instanceof \DateTimeInterface) {
-                $cellXML .= '><v>'.(string) DateHelper::toExcel($value).'</v></c>';
-            } else {
-                throw new InvalidArgumentException('Trying to add a date value with an unsupported type: '.\gettype($value));
-            }
-        } elseif ($cell->isError() && \is_string($cell->getValueEvenIfError())) {
+        } elseif ($cell instanceof Cell\DateTimeCell) {
+            $cellXML .= '><v>'.DateHelper::toExcel($cell->getValue()).'</v></c>';
+        } elseif ($cell instanceof Cell\ErrorCell) {
             // only writes the error value if it's a string
-            $cellXML .= ' t="e"><v>'.$cell->getValueEvenIfError().'</v></c>';
-        } elseif ($cell->isEmpty()) {
+            $cellXML .= ' t="e"><v>'.$cell->getRawValue().'</v></c>';
+        } elseif ($cell instanceof Cell\EmptyCell) {
             if ($this->styleManager->shouldApplyStyleOnEmptyCell($styleId)) {
                 $cellXML .= '/>';
             } else {
@@ -342,8 +220,6 @@ class WorksheetManager implements WorksheetManagerInterface
                 // NOTE: not appending to $cellXML is the right behavior!!
                 $cellXML = '';
             }
-        } else {
-            throw new InvalidArgumentException('Trying to add a value with an unsupported type: '.\gettype($cell->getValue()));
         }
 
         return $cellXML;
@@ -354,17 +230,17 @@ class WorksheetManager implements WorksheetManagerInterface
      *
      * @param string $cellValue The cell value
      *
-     * @throws InvalidArgumentException If the string exceeds the maximum number of characters allowed per cell
-     *
      * @return string The XML fragment representing the cell
+     *
+     * @throws InvalidArgumentException If the string exceeds the maximum number of characters allowed per cell
      */
-    private function getCellXMLFragmentForNonEmptyString($cellValue)
+    private function getCellXMLFragmentForNonEmptyString(string $cellValue): string
     {
         if ($this->stringHelper->getStringLength($cellValue) > self::MAX_CHARACTERS_PER_CELL) {
             throw new InvalidArgumentException('Trying to add a value that exceeds the maximum number of characters allowed in a cell (32,767)');
         }
 
-        if ($this->shouldUseInlineStrings) {
+        if ($this->options->SHOULD_USE_INLINE_STRINGS) {
             $cellXMLFragment = ' t="inlineStr"><is><t>'.$this->stringsEscaper->escape($cellValue).'</t></is></c>';
         } else {
             $sharedStringId = $this->sharedStringsManager->writeString($cellValue);
diff --git a/lib/openspout/src/Writer/XLSX/MergeCell.php b/lib/openspout/src/Writer/XLSX/MergeCell.php
new file mode 100644
index 00000000000..3d342df529f
--- /dev/null
+++ b/lib/openspout/src/Writer/XLSX/MergeCell.php
@@ -0,0 +1,27 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Writer\XLSX;
+
+/**
+ * @internal
+ */
+final class MergeCell
+{
+    /**
+     * @param 0|positive-int $sheetIndex
+     * @param 0|positive-int $topLeftColumn
+     * @param positive-int   $topLeftRow
+     * @param 0|positive-int $bottomRightColumn
+     * @param positive-int   $bottomRightRow
+     */
+    public function __construct(
+        public int $sheetIndex,
+        public int $topLeftColumn,
+        public int $topLeftRow,
+        public int $bottomRightColumn,
+        public int $bottomRightRow,
+    ) {
+    }
+}
diff --git a/lib/openspout/src/Writer/XLSX/Options.php b/lib/openspout/src/Writer/XLSX/Options.php
new file mode 100644
index 00000000000..6bfd2f44419
--- /dev/null
+++ b/lib/openspout/src/Writer/XLSX/Options.php
@@ -0,0 +1,66 @@
+<?php
+
+declare(strict_types=1);
+
+namespace OpenSpout\Writer\XLSX;
+
+use OpenSpout\Common\Entity\Style\Style;
+use OpenSpout\Writer\Common\AbstractOptions;
+
+final class Options extends AbstractOptions
+{
+    public const DEFAULT_FONT_SIZE = 12;
+    public const DEFAULT_FONT_NAME = 'Calibri';
+
+    public bool $SHOULD_USE_INLINE_STRINGS = true;
+
+    /** @var MergeCell[] */
+    private array $MERGE_CELLS = [];
+
+    public function __construct()
+    {
+        parent::__construct();
+
+        $defaultRowStyle = new Style();
+        $defaultRowStyle->setFontSize(self::DEFAULT_FONT_SIZE);
+        $defaultRowStyle->setFontName(self::DEFAULT_FONT_NAME);
+
+        $this->DEFAULT_ROW_STYLE = $defaultRowStyle;
+    }
+
+    /**
+     * Row coordinates are indexed from 1, columns from 0 (A = 0),
+     * so a merge B2:G2 looks like $writer->mergeCells(1, 2, 6, 2);.
+     *
+     * @param 0|positive-int $topLeftColumn
+     * @param positive-int   $topLeftRow
+     * @param 0|positive-int $bottomRightColumn
+     * @param positive-int   $bottomRightRow
+     * @param 0|positive-int $sheetIndex
+     */
+    public function mergeCells(
+        int $topLeftColumn,
+        int $topLeftRow,
+        int $bottomRightColumn,
+        int $bottomRightRow,
+        int $sheetIndex = 0,
+    ): void {
+        $this->MERGE_CELLS[] = new MergeCell(
+            $sheetIndex,
+            $topLeftColumn,
+            $topLeftRow,
+            $bottomRightColumn,
+            $bottomRightRow
+        );
+    }
+
+    /**
+     * @return MergeCell[]
+     *
+     * @internal
+     */
+    public function getMergeCells(): array
+    {
+        return $this->MERGE_CELLS;
+    }
+}
diff --git a/lib/openspout/src/Writer/XLSX/Writer.php b/lib/openspout/src/Writer/XLSX/Writer.php
index fa3a0548ba6..4c4410a5474 100644
--- a/lib/openspout/src/Writer/XLSX/Writer.php
+++ b/lib/openspout/src/Writer/XLSX/Writer.php
@@ -1,72 +1,76 @@
 <?php
 
+declare(strict_types=1);
+
 namespace OpenSpout\Writer\XLSX;
 
-use OpenSpout\Writer\Common\Entity\Options;
-use OpenSpout\Writer\WriterMultiSheetsAbstract;
+use OpenSpout\Common\Helper\Escaper\XLSX;
+use OpenSpout\Common\Helper\StringHelper;
+use OpenSpout\Writer\AbstractWriterMultiSheets;
+use OpenSpout\Writer\Common\Entity\Workbook;
+use OpenSpout\Writer\Common\Helper\ZipHelper;
+use OpenSpout\Writer\Common\Manager\Style\StyleMerger;
+use OpenSpout\Writer\XLSX\Helper\FileSystemHelper;
+use OpenSpout\Writer\XLSX\Manager\CommentsManager;
+use OpenSpout\Writer\XLSX\Manager\SharedStringsManager;
+use OpenSpout\Writer\XLSX\Manager\Style\StyleManager;
+use OpenSpout\Writer\XLSX\Manager\Style\StyleRegistry;
+use OpenSpout\Writer\XLSX\Manager\WorkbookManager;
+use OpenSpout\Writer\XLSX\Manager\WorksheetManager;
 
-/**
- * This class provides base support to write data to XLSX files.
- */
-class Writer extends WriterMultiSheetsAbstract
+final class Writer extends AbstractWriterMultiSheets
 {
     /** @var string Content-Type value for the header */
-    protected static $headerContentType = 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet';
+    protected static string $headerContentType = 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet';
 
-    /**
-     * Sets a custom temporary folder for creating intermediate files/folders.
-     * This must be set before opening the writer.
-     *
-     * @param string $tempFolder Temporary folder where the files to create the XLSX will be stored
-     *
-     * @throws \OpenSpout\Writer\Exception\WriterAlreadyOpenedException If the writer was already opened
-     *
-     * @return Writer
-     */
-    public function setTempFolder($tempFolder)
+    private Options $options;
+
+    public function __construct(?Options $options = null)
     {
-        $this->throwIfWriterAlreadyOpened('Writer must be configured before opening it.');
-
-        $this->optionsManager->setOption(Options::TEMP_FOLDER, $tempFolder);
-
-        return $this;
+        $this->options = $options ?? new Options();
     }
 
-    /**
-     * Use inline string to be more memory efficient. If set to false, it will use shared strings.
-     * This must be set before opening the writer.
-     *
-     * @param bool $shouldUseInlineStrings Whether inline or shared strings should be used
-     *
-     * @throws \OpenSpout\Writer\Exception\WriterAlreadyOpenedException If the writer was already opened
-     *
-     * @return Writer
-     */
-    public function setShouldUseInlineStrings($shouldUseInlineStrings)
+    public function getOptions(): Options
     {
-        $this->throwIfWriterAlreadyOpened('Writer must be configured before opening it.');
-
-        $this->optionsManager->setOption(Options::SHOULD_USE_INLINE_STRINGS, $shouldUseInlineStrings);
-
-        return $this;
+        return $this->options;
     }
 
-    /**
-     * Merge cells.
-     * Row coordinates are indexed from 1, columns from 0 (A = 0),
-     * so a merge B2:G2 looks like $writer->mergeCells([1,2], [6, 2]);.
-     *
-     * You may use CellHelper::getColumnLettersFromColumnIndex() to convert from "B2" to "[1,2]"
-     *
-     * @param int[] $range1 - top left cell's coordinate [column, row]
-     * @param int[] $range2 - bottom right cell's coordinate [column, row]
-     *
-     * @return $this
-     */
-    public function mergeCells(array $range1, array $range2)
+    protected function createWorkbookManager(): WorkbookManager
     {
-        $this->optionsManager->addOption(Options::MERGE_CELLS, [$range1, $range2]);
+        $workbook = new Workbook();
 
-        return $this;
+        $fileSystemHelper = new FileSystemHelper(
+            $this->options->getTempFolder(),
+            new ZipHelper(),
+            new XLSX()
+        );
+        $fileSystemHelper->createBaseFilesAndFolders();
+
+        $xlFolder = $fileSystemHelper->getXlFolder();
+        $sharedStringsManager = new SharedStringsManager($xlFolder, new XLSX());
+
+        $styleMerger = new StyleMerger();
+        $styleManager = new StyleManager(new StyleRegistry($this->options->DEFAULT_ROW_STYLE));
+
+        $commentsManager = new CommentsManager($xlFolder, new XLSX());
+
+        $worksheetManager = new WorksheetManager(
+            $this->options,
+            $styleManager,
+            $styleMerger,
+            $commentsManager,
+            $sharedStringsManager,
+            new XLSX(),
+            StringHelper::factory()
+        );
+
+        return new WorkbookManager(
+            $workbook,
+            $this->options,
+            $worksheetManager,
+            $styleManager,
+            $styleMerger,
+            $fileSystemHelper
+        );
     }
 }
diff --git a/lib/thirdpartylibs.xml b/lib/thirdpartylibs.xml
index 2b190aa5ce6..207b6a35f06 100644
--- a/lib/thirdpartylibs.xml
+++ b/lib/thirdpartylibs.xml
@@ -377,7 +377,7 @@ All rights reserved.</copyright>
     <location>openspout</location>
     <name>OpenSpout</name>
     <description>Library to read and write spreadsheet files (CSV, XLSX and ODS).</description>
-    <version>3.7.3</version>
+    <version>4.13.0</version>
     <license>MIT</license>
     <repository>https://github.com/openspout/openspout</repository>
     <copyrights>