diff --git a/docs/superpowers/specs/2026-06-28-matrix-color-pattern-design.md b/docs/superpowers/specs/2026-06-28-matrix-color-pattern-design.md
new file mode 100644
index 0000000..beee418
--- /dev/null
+++ b/docs/superpowers/specs/2026-06-28-matrix-color-pattern-design.md
@@ -0,0 +1,131 @@
+# Matrix per-color pattern restructure — design
+
+Date: 2026-06-28
+Status: approved (brainstorming), pending implementation plan
+Scope: `sound_algo/data_only/matrix.scd` + `web_realart/public/control/`
+Builds on / restructures: the complete per-instrument editor
+(`2026-06-28-matrix-instrument-editor-design.md`), already on main.
+
+## Goal
+
+Make each matrix color (1-6) a fully autonomous pattern bundling its own
+instrument, 16-step note+velocity sequence, capture effect, and pose binding. The
+matrix grid cell selects which color/pattern plays for a voice at each bar. The
+per-voice effect (mod) and pose bindings — just built — move to per-color. The
+editor modal is reorganized around a color selector + a single per-color pattern
+editor.
+
+## Decisions (from brainstorming)
+
+- 1 color = 1 pattern = { instrument, sequence, effect, pose }, independent per
+  color. The grid cell's color is the live selection.
+- `effect` (capture mod) and `pose` bindings move from per-voice
+  (`~matMod[vi]`/`~matPoseBindings[vi]`) to per-color (fields of
+  `~matColorDefs[vi][color]`).
+- Modal is **color-centric**: a color selector (1-6) at the top, then one pattern
+  editor for the selected color (instrument · variation · this color's 16-step
+  sequence · effect · pose).
+- Backward-compat: legacy `.matrix` files with top-level per-voice `mods`/
+  `poseBindings` migrate on load (a voice's mod copied to all 6 colors; each pose
+  binding routed into its color's pose list). New saves nest mod+pose in colorDefs.
+
+## Data model
+
+`~matColorDefs[vi][color]` (an Event) gains two fields beyond the existing
+`inst, stretch, octave, amp, cutoff, pan, steps`:
+- `mod`: `(source: Sym, target: Sym, depth: Float)` or `nil` (no effect).
+- `pose`: an Array of `(poseId: Sym, action: Sym)` (the color is implicit).
+
+`~matMod` and `~matPoseBindings` (per-voice) are REMOVED. The instrument remains
+`spec[\inst] ? ~matInstruments[vi]` (per-color override, else the voice default).
+
+## Engine (matrix.scd)
+
+- `~matVariationOverlay` and `~matColorStepPattern` read the mod from `spec[\mod]`
+  (the color def) instead of `~matMod[vi]`. The mod→key logic (cutoff/pan/amp via
+  `~matModSourceVal`, neutral cutoff, depth) is unchanged except its source.
+  Factor the mod-key builder into a helper `~matModPairs.(name, spec, volOf)` so
+  both the overlay and the stepped pattern share it (DRY — today it is duplicated).
+- `~matPoseFire.(poseId)` iterates voices × colors × that color's `pose` list:
+  on a match, `\trigger` re-sources the voice to that color now; `\gate` toggles
+  the voice's Pdef. (The binding's color is the color it lives under.)
+- `~matSetColorMod.(vi, color, source, target, depth)` sets/clears
+  `~matColorDefs[vi][color][\mod]` (validate target ∈ `~matModTargets[name]`,
+  source ∈ `~matModSources`; `\none` clears), re-source, echo.
+- `~matSetColorPose.(vi, color, poseId, action)` adds/replaces a pose binding in
+  that color (dedup by poseId; empty poseId clears), echo.
+- Pushes: extend the per-voice editor push so the modal gets each color's mod +
+  pose. Add `~matColorModPush.(vi, color)` → `/matrix/colormod vi color source
+  target depth`; `~matColorPosePush.(vi, color)` → `/matrix/colorpose vi color n
+  <poseId,action>*`. `/matrix/colordefs/get vi` triggers colordefs + steps + mod +
+  pose for all 6 colors.
+
+## OSC contract
+
+| address | dir | payload | meaning |
+|---|---|---|---|
+| `/matrix/colormod` | in/out | vi color source target depth | set/echo a color's effect |
+| `/matrix/colorpose` | in | vi color poseId action | set a color's pose binding |
+| `/matrix/colorpose` | out | vi color n (poseId,action)* | echo a color's pose list |
+| `/matrix/pose` | in | poseId | fire (unchanged) |
+
+The old `/matrix/mod`, `/matrix/posebind`, `/matrix/mods`, `/matrix/poses` (per-voice)
+are removed. `/matrix/instrument`, `/matrix/colordef`, `/matrix/step`,
+`/matrix/audition`, `/matrix/colordefs|steps/get` stay.
+
+## Web (color-centric modal)
+
+Replace the tabbed modal with a color-selector + per-color pattern editor:
+- A row of 6 color buttons (tinted m1-m6); selecting one sets `cdColor`.
+- The pattern editor for `cdColor` shows, stacked:
+  - Instrument `<select>` (curated; sets that color's `inst`).
+  - Variation: stretch / octave / amp / cutoff / pan (filter/pan voices only).
+  - Sequence: a single 16-step row (this color's steps; click toggle, wheel degree,
+    shift+wheel velocity — same interactions as the current grid, one row).
+  - Effect: source / target / depth selects → `/matrix/colormod vi cdColor ...`.
+  - Pose: poseId input + action + add; list of this color's bindings →
+    `/matrix/colorpose vi cdColor ...`.
+- State: `matColorDefs[vi][color]` (JS mirror) gains `mod` + `pose`. WS handlers for
+  `/matrix/colormod`, `/matrix/colorpose` update state + re-render if open on that
+  voice/color. AUDITION toggle (cycle 6 colors) stays.
+- The `matSteps`/`matMod`/`matPoses` JS arrays are folded into `matColorDefs`'
+  per-color `mod`/`pose`/`steps` (single source), persisted under `cdef`.
+
+## Persistence
+
+`.matrix` colorDefs Events now carry `mod` + `pose` (round-trip via
+`asCompileString`). Extend `~matLoadFile`'s colorDefs allow-list to copy `mod`
+(Event) and `pose` (Array). Migration: when a legacy Event has top-level `mods`
+(16 per-voice) → copy each voice's mod into all 6 of its colors' `mod`; top-level
+`poseBindings` (16 lists of (poseId,action,color)) → route each into
+`colorDefs[vi][color][\pose]`. localStorage `cdef` carries mod+pose per color;
+drop the separate `steps`/`pose`/`mod` localStorage keys (folded into `cdef`).
+
+## Error handling / robustness
+
+- Setters validate ranges and membership (target ∈ voice's `~matModTargets`,
+  source ∈ `~matModSources`); invalid → ignored.
+- Empty `mod`/`pose` (nil / empty list) = no effect / no binding — default state.
+- `/matrix/pose` unknown id → no match → no-op.
+- nil-guarded, idempotent reload; defaults reproduce current behavior (empty
+  mod/pose ⇒ same as today's no-mod path).
+
+## Testing
+
+- **SC** (`test_matrix.scd`, headless, P:0 B:0):
+  - colorDefs default `mod` nil + `pose` empty; `~matSetColorMod`/`~matSetColorPose`
+    set + validate + echo; a stepped/overlay pattern reads the color's mod (cutoff
+    target → `\cutoff` key present when set, absent when nil).
+  - `~matPoseFire` fires a per-color binding (trigger re-sources the right color);
+    unknown id no-op.
+  - persistence round-trip of per-color mod+pose; legacy per-voice `mods`/
+    `poseBindings` migrate into colorDefs on load.
+- **Web**: `node --check`; manual — color selector switches the pattern editor;
+  editing a color's instrument/variation/sequence/effect/pose round-trips and only
+  affects that color; audition cycles colors.
+
+## Out of scope
+
+- Pose recognition (still consumes `/matrix/pose <poseId>`).
+- Per-step effect/pose (effect+pose are per-color, not per-step); variable step
+  counts; cross-color linking.