diff --git a/CHANGELOG.md b/CHANGELOG.md
index e45e35e..a78d9d8 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@ Follows [Keep a Changelog](https://keepachangelog.com/en/1.0.0/) · versioned wi
## [Unreleased]
### Changed
+- **Rehearser voice-design extraction.** Character development, backend selection, and backend-refresh synchronization
+ now live in `rehearser-voice-design.js` while preserving the existing cast controls and global API.
- **Voice Design stylesheet split.** Voice-design form, sample-grid, and preview-match rules now live in
`static/css/voice-design.css`.
- **Background-job stylesheet split.** Job history and retry-panel rules now live in `static/css/background-jobs.css`.
diff --git a/TODO.md b/TODO.md
index 54d2f6d..73d2ce2 100644
--- a/TODO.md
+++ b/TODO.md
@@ -132,6 +132,7 @@ architecture change: the larger Audiobook/Rehearser/style split.
- [x] Extract Rehearser voice-picker presentation and preview state into `rehearser-voice-picker.js`.
- [x] Extract Rehearser cast view, sorting, filtering, and toolbar wiring into `rehearser-cast.js`.
- [x] Extract Rehearser training transcript comparison helpers into `rehearser-train.js`.
+- [x] Extract Rehearser character development and backend-selection controls into `rehearser-voice-design.js`.
- [x] Extract Rehearser library persistence and IndexedDB migration into `rehearser-library.js`.
- [ ] Extract Audiobook parsing and casting.
- [x] Extract Audiobook parsing primitives and speaker-heuristic constants into `audiobook-parse.js`.
diff --git a/VERSION b/VERSION
index 68eebc0..fb56e1f 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.24.36
+1.24.37
diff --git a/docs/ARCHITECTURE.md b/docs/ARCHITECTURE.md
index 577a6c9..97273d7 100644
--- a/docs/ARCHITECTURE.md
+++ b/docs/ARCHITECTURE.md
@@ -34,6 +34,7 @@ Done incrementally as global-scope ordered files (no ES-module change needed)
- ✅ `rehearser-stage.js` — stage font/cast sidebar controls and cast-strip rendering; playback and transport remain in `rehearser.js`.
- ✅ `rehearser-voice-picker.js` — voice preview state and matched-choice presentation; import and assignment actions remain in `rehearser.js`.
- ✅ `rehearser-cast.js` — cast view, sort/filter state handlers, and cast toolbar wiring; card rendering remains in `rehearser.js`.
+- ✅ `rehearser-voice-design.js` — character development, backend selection, and backend-refresh synchronization.
- ✅ `audiobook-parse.js` — dialogue detection, dehyphenation, and speaker-heuristic constants; the casting pipeline remains in `audiobook.js`.
- ✅ `audiobook-cast.js` — cast Markdown export and legacy page-stamping migration helpers; live casting remains in `audiobook.js`.
- ✅ `static/css/resource-diagnostics.css` — isolated Performance/resource diagnostic panel styles.
diff --git a/static/index.html b/static/index.html
index 3aad0d1..ee6ceec 100644
--- a/static/index.html
+++ b/static/index.html
@@ -10,7 +10,7 @@
-
+
@@ -27,10 +27,10 @@
-
-
-
-
+
+
+
+
@@ -395,7 +395,7 @@ window.toggleNavTree = function(treeId, chevronId) {
-
+