chore(release): 4.0.0 [skip ci]

## [4.0.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.24.0...v4.0.0) (2025-10-16)

### ⚠ BREAKING CHANGES

* **db:** Database schemas now accept any string for game names

### Code Refactoring

* **db:** remove database schema coupling for game names ([e135d92](e135d92abb)), closes [#1](https://github.com/antialias/soroban-abacus-flashcards/issues/1)

CHANGELOG.md

@@ -1,3 +1,206 @@
+## [4.0.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.24.0...v4.0.0) (2025-10-16)
+
+
+### ⚠ BREAKING CHANGES
+
+* **db:** Database schemas now accept any string for game names
+
+### Code Refactoring
+
+* **db:** remove database schema coupling for game names ([e135d92](https://github.com/antialias/soroban-abacus-flashcards/commit/e135d92abb4d27f646c1fbeff6524a729d107426)), closes [#1](https://github.com/antialias/soroban-abacus-flashcards/issues/1)
+
+## [3.24.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.23.0...v3.24.0) (2025-10-16)
+
+
+### Features
+
+* **math-sprint:** add game manifest ([1eefcc8](https://github.com/antialias/soroban-abacus-flashcards/commit/1eefcc89a58b79f928932a7425d6b88fb45a5526))
+
+## [3.23.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.22.3...v3.23.0) (2025-10-16)
+
+
+### Features
+
+* **arcade:** add Math Sprint game implementation ([e5be09e](https://github.com/antialias/soroban-abacus-flashcards/commit/e5be09ef5f170c7544557f75b9eca17bb2069246))
+* **arcade:** register Math Sprint in game system ([0c05a7c](https://github.com/antialias/soroban-abacus-flashcards/commit/0c05a7c6bbc8d6f6e1f92e15e691d7e1aba0d8f7)), closes [#2](https://github.com/antialias/soroban-abacus-flashcards/issues/2) [#3](https://github.com/antialias/soroban-abacus-flashcards/issues/3)
+
+
+### Bug Fixes
+
+* **api:** add 'math-sprint' to settings endpoint validation ([d790e5e](https://github.com/antialias/soroban-abacus-flashcards/commit/d790e5e278f81686077dbe3ef4adca49574ae434)), closes [#1](https://github.com/antialias/soroban-abacus-flashcards/issues/1)
+* **db:** add 'math-sprint' to database schema enums ([7b112a9](https://github.com/antialias/soroban-abacus-flashcards/commit/7b112a98babe782d4c254ef18a0295e7cbf8fefa)), closes [#1](https://github.com/antialias/soroban-abacus-flashcards/issues/1)
+
+
+### Documentation
+
+* add architecture quality audit [#2](https://github.com/antialias/soroban-abacus-flashcards/issues/2) ([5b91b71](https://github.com/antialias/soroban-abacus-flashcards/commit/5b91b710782dc450405583bc196e5156a296d0df))
+
+## [3.22.3](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.22.2...v3.22.3) (2025-10-16)
+
+
+### Bug Fixes
+
+* **number-guesser:** add turn indicators, error feedback, and fix player ordering ([9f62623](https://github.com/antialias/soroban-abacus-flashcards/commit/9f626236845493ef68e1b3626e80efa35637b449))
+
+
+### Documentation
+
+* **arcade:** update docs for unified validator registry ([6f6cb14](https://github.com/antialias/soroban-abacus-flashcards/commit/6f6cb14650ba3636a7e2b036e2a2a9410492e7c3))
+
+## [3.22.2](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.22.1...v3.22.2) (2025-10-16)
+
+
+### Code Refactoring
+
+* **arcade:** create unified validator registry to fix dual registration ([f775fc5](https://github.com/antialias/soroban-abacus-flashcards/commit/f775fc55e50af0c3a29b3e00fc722e7d7ce90212)), closes [#1](https://github.com/antialias/soroban-abacus-flashcards/issues/1)
+
+## [3.22.1](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.22.0...v3.22.1) (2025-10-16)
+
+
+### Bug Fixes
+
+* **arcade:** add Number Guesser to game config helpers ([7d1a351](https://github.com/antialias/soroban-abacus-flashcards/commit/7d1a351ed6a1442ae34f6b75d46039bfa77a921b))
+* **nav:** update types for registry games with nullable gameName ([a51e539](https://github.com/antialias/soroban-abacus-flashcards/commit/a51e539d023681daf639ec104e79079c8ceec98e))
+
+## [3.22.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.21.0...v3.22.0) (2025-10-16)
+
+
+### Features
+
+* **arcade:** add Number Guesser demo game with plugin architecture ([0e3c058](https://github.com/antialias/soroban-abacus-flashcards/commit/0e3c0587073a69574a50f05c467f2499296012bf))
+
+## [3.21.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.20.0...v3.21.0) (2025-10-15)
+
+
+### Features
+
+* **arcade:** add modular game SDK and registry system ([de30bec](https://github.com/antialias/soroban-abacus-flashcards/commit/de30bec47923565fe5d1d5a6f719f3fc4e9d1509))
+
+## [3.20.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.19.0...v3.20.0) (2025-10-15)
+
+
+### Features
+
+* adjust tier probabilities for more abacus flavor ([49219e3](https://github.com/antialias/soroban-abacus-flashcards/commit/49219e34cde32736155a11929d10581e783cba69))
+
+
+### Code Refactoring
+
+* use per-word-type tier selection for name generation ([499ee52](https://github.com/antialias/soroban-abacus-flashcards/commit/499ee525a835249b439044cf602bf9f0ff322cec))
+
+## [3.19.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.18.1...v3.19.0) (2025-10-15)
+
+
+### Features
+
+* implement avatar-themed name generation with probabilistic mixing ([76a8472](https://github.com/antialias/soroban-abacus-flashcards/commit/76a8472f12d251071b97f2288f62f0b358576232))
+
+## [3.18.1](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.18.0...v3.18.1) (2025-10-15)
+
+
+### Bug Fixes
+
+* **arcade:** prevent empty update in settings API when only gameConfig changes ([ffb626f](https://github.com/antialias/soroban-abacus-flashcards/commit/ffb626f4038fd32d0f40dba8d83ae4d881d698d0))
+
+## [3.18.0](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.14...v3.18.0) (2025-10-15)
+
+
+### Features
+
+* add drizzle migration for room_game_configs table ([3bae00b](https://github.com/antialias/soroban-abacus-flashcards/commit/3bae00b9a9dc925039a02fe07d036a2fc5e0fb79))
+
+
+### Documentation
+
+* document manual migration of room_game_configs table ([ff79140](https://github.com/antialias/soroban-abacus-flashcards/commit/ff791409cf4bae1a5df43eb974eacbc7612d8eec))
+
+## [3.17.14](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.13...v3.17.14) (2025-10-15)
+
+
+### Bug Fixes
+
+* **arcade:** resolve TypeScript errors in game config helpers ([04c9944](https://github.com/antialias/soroban-abacus-flashcards/commit/04c9944f2ed1025f5a4ece61761889edd08cc60d))
+
+
+### Documentation
+
+* **arcade:** update GAME_SETTINGS_PERSISTENCE.md for new schema ([260bdc2](https://github.com/antialias/soroban-abacus-flashcards/commit/260bdc2e9d458cb42a96d3ed36a18134260b4520))
+
+## [3.17.13](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.12...v3.17.13) (2025-10-15)
+
+
+### Code Refactoring
+
+* **arcade:** migrate game settings to normalized database schema ([1bd7354](https://github.com/antialias/soroban-abacus-flashcards/commit/1bd73544df6d62416961eea0b358955aaf82b79d))
+
+## [3.17.12](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.11...v3.17.12) (2025-10-15)
+
+
+### Code Refactoring
+
+* **arcade:** remove non-productive debug logging from memory-quiz ([38e554e](https://github.com/antialias/soroban-abacus-flashcards/commit/38e554e6ea0386e48798338dd938e50ba73d5576))
+
+
+### Documentation
+
+* **arcade:** document game settings persistence architecture ([8f8f112](https://github.com/antialias/soroban-abacus-flashcards/commit/8f8f112de222e40901d4b3168fa751d233337e4b))
+
+## [3.17.11](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.10...v3.17.11) (2025-10-15)
+
+
+### Bug Fixes
+
+* **memory-quiz:** fix playMode persistence by updating validator ([de0efd5](https://github.com/antialias/soroban-abacus-flashcards/commit/de0efd59321ec779cddb900724035884290419b7))
+
+## [3.17.10](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.9...v3.17.10) (2025-10-15)
+
+
+### Bug Fixes
+
+* **memory-quiz:** persist playMode setting across game switches ([487ca7f](https://github.com/antialias/soroban-abacus-flashcards/commit/487ca7fba62e370c85bc3779ca8a96eb2c2cc3e3))
+
+## [3.17.9](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.8...v3.17.9) (2025-10-15)
+
+
+### Bug Fixes
+
+* **arcade:** read nested gameConfig correctly when creating sessions ([94ef392](https://github.com/antialias/soroban-abacus-flashcards/commit/94ef39234d362b82e032cb69d3561b9fcb436eaf))
+
+## [3.17.8](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.7...v3.17.8) (2025-10-15)
+
+
+### Bug Fixes
+
+* **arcade:** preserve game settings when returning to game selection ([0ee7739](https://github.com/antialias/soroban-abacus-flashcards/commit/0ee7739091d60580d2f98cfe288b8586b03348f3))
+
+## [3.17.7](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.6...v3.17.7) (2025-10-15)
+
+
+### Bug Fixes
+
+* **arcade:** prevent gameConfig from being overwritten when switching games ([a89d3a9](https://github.com/antialias/soroban-abacus-flashcards/commit/a89d3a970137471e2652de992c45370dbb97416d))
+
+## [3.17.6](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.5...v3.17.6) (2025-10-15)
+
+
+### Code Refactoring
+
+* **logging:** use JSON.stringify for all object logging ([c33698c](https://github.com/antialias/soroban-abacus-flashcards/commit/c33698ce52ebdc18ce3a0d856f9241c7389ed651))
+
+## [3.17.5](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.4...v3.17.5) (2025-10-15)
+
+
+### Bug Fixes
+
+* **arcade:** implement settings persistence for matching game ([08fe432](https://github.com/antialias/soroban-abacus-flashcards/commit/08fe4326a6a7c484b9058a241f4ff79b3fb5125f))
+
+## [3.17.4](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.3...v3.17.4) (2025-10-15)
+
+
+### Bug Fixes
+
+* **matching:** add settings persistence to matching game ([00dcb87](https://github.com/antialias/soroban-abacus-flashcards/commit/00dcb872b7e70bdb7de301b56fe42195e6ee923f))
+
 ## [3.17.3](https://github.com/antialias/soroban-abacus-flashcards/compare/v3.17.2...v3.17.3) (2025-10-15)
 
 

apps/web/.claude/CLAUDE.md

@@ -108,3 +108,31 @@ npm run check          # Biome check (format + lint + organize imports)
 - Lint checks
 
 **Status:** Known issue, does not block development or deployment.
+
+## Game Settings Persistence
+
+When working on arcade room game settings, refer to:
+
+- **`.claude/GAME_SETTINGS_PERSISTENCE.md`** - Complete architecture documentation
+  - How settings are stored (nested by game name)
+  - Three critical systems that must stay in sync
+  - Common bugs and their solutions
+  - Debugging checklist
+  - Step-by-step guide for adding new settings
+
+- **`.claude/GAME_SETTINGS_REFACTORING.md`** - Recommended improvements
+  - Shared config types to prevent inconsistencies
+  - Helper functions to reduce duplication
+  - Type-safe validation
+  - Migration strategy
+
+**Quick Reference:**
+
+Settings are stored as: `gameConfig[gameName][setting]`
+
+Three places must handle settings correctly:
+1. **Provider** (`Room{Game}Provider.tsx`) - Merges saved config with defaults
+2. **Socket Server** (`socket-server.ts`) - Creates session from saved config
+3. **Validator** (`{Game}Validator.ts`) - `getInitialState()` must accept ALL settings
+
+If a setting doesn't persist, check all three locations.

apps/web/.claude/GAME_SETTINGS_PERSISTENCE.md

@@ -0,0 +1,421 @@
+# Game Settings Persistence Architecture
+
+## Overview
+
+Game settings in room mode persist across game switches using a normalized database schema. Settings for each game are stored in a dedicated `room_game_configs` table with one row per game per room.
+
+## Database Schema
+
+Settings are stored in the `room_game_configs` table:
+
+```sql
+CREATE TABLE room_game_configs (
+  id TEXT PRIMARY KEY,
+  room_id TEXT NOT NULL REFERENCES arcade_rooms(id) ON DELETE CASCADE,
+  game_name TEXT NOT NULL CHECK(game_name IN ('matching', 'memory-quiz', 'complement-race')),
+  config TEXT NOT NULL,  -- JSON
+  created_at INTEGER NOT NULL,
+  updated_at INTEGER NOT NULL,
+  UNIQUE(room_id, game_name)
+);
+```
+
+**Benefits:**
+- ✅ Type-safe config access with shared types
+- ✅ Smaller rows (only configs for games that have been used)
+- ✅ Easier updates (single row vs entire JSON blob)
+- ✅ Better concurrency (no lock contention between games)
+- ✅ Foundation for per-game audit trail
+- ✅ Can query/index individual game settings
+
+**Example Row:**
+```json
+{
+  "id": "clxyz123",
+  "room_id": "room_abc",
+  "game_name": "memory-quiz",
+  "config": {
+    "selectedCount": 8,
+    "displayTime": 3.0,
+    "selectedDifficulty": "medium",
+    "playMode": "competitive"
+  },
+  "created_at": 1234567890,
+  "updated_at": 1234567890
+}
+```
+
+## Shared Type System
+
+All game configs are defined in `src/lib/arcade/game-configs.ts`:
+
+```typescript
+// Shared config types (single source of truth)
+export interface MatchingGameConfig {
+  gameType: 'abacus-numeral' | 'complement-pairs'
+  difficulty: number
+  turnTimer: number
+}
+
+export interface MemoryQuizGameConfig {
+  selectedCount: 2 | 5 | 8 | 12 | 15
+  displayTime: number
+  selectedDifficulty: DifficultyLevel
+  playMode: 'cooperative' | 'competitive'
+}
+
+// Default configs
+export const DEFAULT_MATCHING_CONFIG: MatchingGameConfig = {
+  gameType: 'abacus-numeral',
+  difficulty: 6,
+  turnTimer: 30,
+}
+
+export const DEFAULT_MEMORY_QUIZ_CONFIG: MemoryQuizGameConfig = {
+  selectedCount: 5,
+  displayTime: 2.0,
+  selectedDifficulty: 'easy',
+  playMode: 'cooperative',
+}
+```
+
+**Why This Matters:**
+- TypeScript enforces that validators, helpers, and API routes all use the same types
+- Adding a new setting requires changes in only ONE place (the type definition)
+- Impossible to forget a setting or use wrong type
+
+## Critical Components
+
+Settings persistence requires coordination between FOUR systems:
+
+### 1. Helper Functions
+**Location:** `src/lib/arcade/game-config-helpers.ts`
+
+**Responsibilities:**
+- Read/write game configs from `room_game_configs` table
+- Provide type-safe access with automatic defaults
+- Validate configs at runtime
+
+**Key Functions:**
+```typescript
+// Get config with defaults (type-safe)
+const config = await getGameConfig(roomId, 'memory-quiz')
+// Returns: MemoryQuizGameConfig
+
+// Set/update config (upsert)
+await setGameConfig(roomId, 'memory-quiz', {
+  playMode: 'competitive',
+  selectedCount: 8,
+})
+
+// Get all game configs for a room
+const allConfigs = await getAllGameConfigs(roomId)
+// Returns: { matching?: MatchingGameConfig, 'memory-quiz'?: MemoryQuizGameConfig }
+```
+
+### 2. API Routes
+**Location:**
+- `src/app/api/arcade/rooms/current/route.ts` (read)
+- `src/app/api/arcade/rooms/[roomId]/settings/route.ts` (write)
+
+**Responsibilities:**
+- Aggregate game configs from database
+- Return them to client in `room.gameConfig`
+- Write config updates to `room_game_configs` table
+
+**Read Example:** `GET /api/arcade/rooms/current`
+```typescript
+const gameConfig = await getAllGameConfigs(roomId)
+
+return NextResponse.json({
+  room: {
+    ...room,
+    gameConfig, // Aggregated from room_game_configs table
+  },
+  members,
+  memberPlayers,
+})
+```
+
+**Write Example:** `PATCH /api/arcade/rooms/[roomId]/settings`
+```typescript
+if (body.gameConfig !== undefined) {
+  // body.gameConfig: { matching: {...}, memory-quiz: {...} }
+  for (const [gameName, config] of Object.entries(body.gameConfig)) {
+    await setGameConfig(roomId, gameName, config)
+  }
+}
+```
+
+### 3. Socket Server (Session Creation)
+**Location:** `src/socket-server.ts:70-90`
+
+**Responsibilities:**
+- Create initial arcade session when user joins room
+- Read saved settings using `getGameConfig()` helper
+- Pass settings to validator's `getInitialState()`
+
+**Example:**
+```typescript
+const room = await getRoomById(roomId)
+const validator = getValidator(room.gameName as GameName)
+
+// Get config from database (type-safe, includes defaults)
+const gameConfig = await getGameConfig(roomId, room.gameName as GameName)
+
+// Pass to validator (types match automatically)
+const initialState = validator.getInitialState(gameConfig)
+
+await createArcadeSession({ userId, gameName, initialState, roomId })
+```
+
+**Key Point:** No more manual config extraction or default fallbacks!
+
+### 4. Game Validators
+**Location:** `src/lib/arcade/validation/*Validator.ts`
+
+**Responsibilities:**
+- Define `getInitialState()` method with shared config type
+- Create initial game state from config
+- TypeScript enforces all settings are handled
+
+**Example:** `MemoryQuizGameValidator.ts`
+```typescript
+import type { MemoryQuizGameConfig } from '@/lib/arcade/game-configs'
+
+class MemoryQuizGameValidator {
+  getInitialState(config: MemoryQuizGameConfig): SorobanQuizState {
+    return {
+      selectedCount: config.selectedCount,
+      displayTime: config.displayTime,
+      selectedDifficulty: config.selectedDifficulty,
+      playMode: config.playMode,  // TypeScript ensures this field exists!
+      // ...other state
+    }
+  }
+}
+```
+
+### 5. Client Providers (Unchanged)
+**Location:** `src/app/arcade/{game}/context/Room{Game}Provider.tsx`
+
+**Responsibilities:**
+- Read settings from `roomData.gameConfig[gameName]`
+- Merge with `initialState` defaults
+- Works transparently with new backend structure
+
+**Example:** `RoomMemoryQuizProvider.tsx:211-233`
+```typescript
+const mergedInitialState = useMemo(() => {
+  const gameConfig = roomData?.gameConfig as Record<string, any>
+  const savedConfig = gameConfig?.['memory-quiz']
+
+  if (!savedConfig) {
+    return initialState
+  }
+
+  return {
+    ...initialState,
+    selectedCount: savedConfig.selectedCount ?? initialState.selectedCount,
+    displayTime: savedConfig.displayTime ?? initialState.displayTime,
+    selectedDifficulty: savedConfig.selectedDifficulty ?? initialState.selectedDifficulty,
+    playMode: savedConfig.playMode ?? initialState.playMode,
+  }
+}, [roomData?.gameConfig])
+```
+
+## Common Bugs and Solutions
+
+### Bug #1: Settings Not Persisting
+**Symptom:** Settings reset to defaults after game switch
+
+**Root Cause:** One of the following:
+1. API route not writing to `room_game_configs` table
+2. Helper function not being used correctly
+3. Validator not using shared config type
+
+**Solution:** Verify the data flow:
+```bash
+# 1. Check database write
+SELECT * FROM room_game_configs WHERE room_id = '...';
+
+# 2. Check API logs for setGameConfig() calls
+# Look for: [GameConfig] Updated {game} config for room {roomId}
+
+# 3. Check socket server logs for getGameConfig() calls
+# Look for: [join-arcade-session] Got validator for: {game}
+
+# 4. Check validator signature matches shared type
+# MemoryQuizGameValidator.getInitialState(config: MemoryQuizGameConfig)
+```
+
+### Bug #2: TypeScript Errors About Missing Fields
+**Symptom:** `Property '{field}' is missing in type ...`
+
+**Root Cause:** Validator's `getInitialState()` signature doesn't match shared config type
+
+**Solution:** Import and use the shared config type:
+```typescript
+// ❌ WRONG
+getInitialState(config: {
+  selectedCount: number
+  displayTime: number
+  // Missing playMode!
+}): SorobanQuizState
+
+// ✅ CORRECT
+import type { MemoryQuizGameConfig } from '@/lib/arcade/game-configs'
+
+getInitialState(config: MemoryQuizGameConfig): SorobanQuizState
+```
+
+### Bug #3: Settings Wiped When Returning to Game Selection
+**Symptom:** Settings reset when going back to game selection
+
+**Root Cause:** Sending `gameConfig: null` in PATCH request
+
+**Solution:** Only send `gameName: null`, don't touch gameConfig:
+```typescript
+// ❌ WRONG
+body: JSON.stringify({ gameName: null, gameConfig: null })
+
+// ✅ CORRECT
+body: JSON.stringify({ gameName: null })
+```
+
+## Debugging Checklist
+
+When a setting doesn't persist:
+
+1. **Check database:**
+   - Query `room_game_configs` table
+   - Verify row exists for room + game
+   - Verify JSON config has correct structure
+
+2. **Check API write path:**
+   - `/api/arcade/rooms/[roomId]/settings` logs
+   - Verify `setGameConfig()` is called
+   - Check for errors in console
+
+3. **Check API read path:**
+   - `/api/arcade/rooms/current` logs
+   - Verify `getAllGameConfigs()` returns data
+   - Check `room.gameConfig` in response
+
+4. **Check socket server:**
+   - `socket-server.ts` logs for `getGameConfig()`
+   - Verify config passed to validator
+   - Check `initialState` has correct values
+
+5. **Check validator:**
+   - Signature uses shared config type
+   - All config fields used (not hardcoded)
+   - Add logging to see received config
+
+## Adding a New Setting
+
+To add a new setting to an existing game:
+
+1. **Update the shared config type** (`game-configs.ts`):
+```typescript
+export interface MemoryQuizGameConfig {
+  selectedCount: 2 | 5 | 8 | 12 | 15
+  displayTime: number
+  selectedDifficulty: DifficultyLevel
+  playMode: 'cooperative' | 'competitive'
+  newSetting: string  // ← Add here
+}
+
+export const DEFAULT_MEMORY_QUIZ_CONFIG: MemoryQuizGameConfig = {
+  selectedCount: 5,
+  displayTime: 2.0,
+  selectedDifficulty: 'easy',
+  playMode: 'cooperative',
+  newSetting: 'default',  // ← Add default
+}
+```
+
+2. **TypeScript will now enforce:**
+   - ✅ Validator must accept `newSetting` (compile error if missing)
+   - ✅ Helper functions will include it automatically
+   - ✅ Client providers will need to handle it
+
+3. **Update the validator** (`*Validator.ts`):
+```typescript
+getInitialState(config: MemoryQuizGameConfig): SorobanQuizState {
+  return {
+    // ...
+    newSetting: config.newSetting,  // TypeScript enforces this
+  }
+}
+```
+
+4. **Update the UI** to expose the new setting
+   - No changes needed to API routes or helper functions!
+   - They automatically handle any field in the config type
+
+## Testing Settings Persistence
+
+Manual test procedure:
+
+1. Join a room and select a game
+2. Change each setting to a non-default value
+3. Go back to game selection (gameName becomes null)
+4. Select the same game again
+5. **Verify ALL settings retained their values**
+
+**Expected behavior:** All settings should be exactly as you left them.
+
+## Migration Notes
+
+**Old Schema:**
+- Settings stored in `arcade_rooms.game_config` JSON column
+- Config stored directly for currently selected game only
+- Config lost when switching games
+
+**New Schema:**
+- Settings stored in `room_game_configs` table
+- One row per game per room
+- Unique constraint on (room_id, game_name)
+- Configs persist when switching between games
+
+**Migration:** See `.claude/MANUAL_MIGRATION_0011.md` for complete details
+
+**Summary:**
+- Manual migration applied on 2025-10-15
+- Created `room_game_configs` table via sqlite3 CLI
+- Migrated 6000 existing configs (5991 matching, 9 memory-quiz)
+- Table created directly instead of through drizzle migration system
+
+**Rollback Plan:**
+- Old `game_config` column still exists in `arcade_rooms` table
+- Old data preserved (was only read, not deleted)
+- Can revert to reading from old column if needed
+- New table can be dropped: `DROP TABLE room_game_configs`
+
+## Architecture Benefits
+
+**Type Safety:**
+- Single source of truth for config types
+- TypeScript enforces consistency everywhere
+- Impossible to forget a setting
+
+**DRY (Don't Repeat Yourself):**
+- No duplicated default values
+- No manual config extraction
+- No manual merging with defaults
+
+**Maintainability:**
+- Adding a setting touches fewer places
+- Clear separation of concerns
+- Easier to trace data flow
+
+**Performance:**
+- Smaller database rows
+- Better query performance
+- Less network payload
+
+**Correctness:**
+- Runtime validation available
+- Database constraints (unique index)
+- Impossible to create duplicate configs

apps/web/.claude/GAME_SETTINGS_REFACTORING.md

@@ -0,0 +1,479 @@
+# Game Settings Persistence - Refactoring Recommendations
+
+## Current Pain Points
+
+1. **Type safety is weak** - Easy to forget to add a setting in one place
+2. **Duplication** - Config reading logic duplicated in socket-server.ts for each game
+3. **Manual synchronization** - Have to manually keep validator signature, provider, and socket server in sync
+4. **Error-prone** - Easy to hardcode values or forget to read from config
+
+## Recommended Refactorings
+
+### 1. Create Shared Config Types (HIGHEST PRIORITY)
+
+**Problem:** Each game's settings are defined in multiple places with no type enforcement
+
+**Solution:** Define a single source of truth for each game's config
+
+```typescript
+// src/lib/arcade/game-configs.ts
+
+export interface MatchingGameConfig {
+  gameType: 'abacus-numeral' | 'complement-pairs'
+  difficulty: number
+  turnTimer: number
+}
+
+export interface MemoryQuizGameConfig {
+  selectedCount: 2 | 5 | 8 | 12 | 15
+  displayTime: number
+  selectedDifficulty: DifficultyLevel
+  playMode: 'cooperative' | 'competitive'
+}
+
+export interface ComplementRaceGameConfig {
+  // ... future settings
+}
+
+export interface RoomGameConfig {
+  matching?: MatchingGameConfig
+  'memory-quiz'?: MemoryQuizGameConfig
+  'complement-race'?: ComplementRaceGameConfig
+}
+
+// Default configs
+export const DEFAULT_MATCHING_CONFIG: MatchingGameConfig = {
+  gameType: 'abacus-numeral',
+  difficulty: 6,
+  turnTimer: 30,
+}
+
+export const DEFAULT_MEMORY_QUIZ_CONFIG: MemoryQuizGameConfig = {
+  selectedCount: 5,
+  displayTime: 2.0,
+  selectedDifficulty: 'easy',
+  playMode: 'cooperative',
+}
+```
+
+**Benefits:**
+- Single source of truth for each game's settings
+- TypeScript enforces consistency across codebase
+- Easy to see what settings each game has
+
+### 2. Create Config Helper Functions
+
+**Problem:** Config reading logic is duplicated and error-prone
+
+**Solution:** Centralized helper functions with type safety
+
+```typescript
+// src/lib/arcade/game-config-helpers.ts
+
+import type { GameName } from './validation'
+import type { RoomGameConfig, MatchingGameConfig, MemoryQuizGameConfig } from './game-configs'
+import { DEFAULT_MATCHING_CONFIG, DEFAULT_MEMORY_QUIZ_CONFIG } from './game-configs'
+
+/**
+ * Get game-specific config from room's gameConfig with defaults
+ */
+export function getGameConfig<T extends GameName>(
+  roomGameConfig: RoomGameConfig | null | undefined,
+  gameName: T
+): T extends 'matching'
+  ? MatchingGameConfig
+  : T extends 'memory-quiz'
+  ? MemoryQuizGameConfig
+  : never {
+
+  if (!roomGameConfig) {
+    return getDefaultGameConfig(gameName) as any
+  }
+
+  const savedConfig = roomGameConfig[gameName]
+  if (!savedConfig) {
+    return getDefaultGameConfig(gameName) as any
+  }
+
+  // Merge saved config with defaults to handle missing fields
+  const defaults = getDefaultGameConfig(gameName)
+  return { ...defaults, ...savedConfig } as any
+}
+
+function getDefaultGameConfig(gameName: GameName) {
+  switch (gameName) {
+    case 'matching':
+      return DEFAULT_MATCHING_CONFIG
+    case 'memory-quiz':
+      return DEFAULT_MEMORY_QUIZ_CONFIG
+    case 'complement-race':
+      // return DEFAULT_COMPLEMENT_RACE_CONFIG
+      throw new Error('complement-race config not implemented')
+    default:
+      throw new Error(`Unknown game: ${gameName}`)
+  }
+}
+
+/**
+ * Update a specific game's config in the room's gameConfig
+ */
+export function updateGameConfig<T extends GameName>(
+  currentRoomConfig: RoomGameConfig | null | undefined,
+  gameName: T,
+  updates: Partial<T extends 'matching' ? MatchingGameConfig : T extends 'memory-quiz' ? MemoryQuizGameConfig : never>
+): RoomGameConfig {
+  const current = currentRoomConfig || {}
+  const gameConfig = current[gameName] || getDefaultGameConfig(gameName)
+
+  return {
+    ...current,
+    [gameName]: {
+      ...gameConfig,
+      ...updates,
+    },
+  }
+}
+```
+
+**Usage in socket-server.ts:**
+```typescript
+// BEFORE (error-prone, duplicated)
+const memoryQuizConfig = (room.gameConfig as any)?.['memory-quiz'] || {}
+initialState = validator.getInitialState({
+  selectedCount: memoryQuizConfig.selectedCount || 5,
+  displayTime: memoryQuizConfig.displayTime || 2.0,
+  selectedDifficulty: memoryQuizConfig.selectedDifficulty || 'easy',
+  playMode: memoryQuizConfig.playMode || 'cooperative',
+})
+
+// AFTER (type-safe, concise)
+const config = getGameConfig(room.gameConfig, 'memory-quiz')
+initialState = validator.getInitialState(config)
+```
+
+**Usage in RoomMemoryQuizProvider.tsx:**
+```typescript
+// BEFORE (verbose, error-prone)
+const mergedInitialState = useMemo(() => {
+  const gameConfig = roomData?.gameConfig as Record<string, any>
+  const savedConfig = gameConfig?.['memory-quiz']
+
+  return {
+    ...initialState,
+    selectedCount: savedConfig?.selectedCount ?? initialState.selectedCount,
+    displayTime: savedConfig?.displayTime ?? initialState.displayTime,
+    selectedDifficulty: savedConfig?.selectedDifficulty ?? initialState.selectedDifficulty,
+    playMode: savedConfig?.playMode ?? initialState.playMode,
+  }
+}, [roomData?.gameConfig])
+
+// AFTER (type-safe, concise)
+const mergedInitialState = useMemo(() => {
+  const config = getGameConfig(roomData?.gameConfig, 'memory-quiz')
+  return {
+    ...initialState,
+    ...config,  // Spread config directly - all settings included
+  }
+}, [roomData?.gameConfig])
+```
+
+**Benefits:**
+- No more manual property-by-property merging
+- Type-safe
+- Defaults handled automatically
+- Reusable across codebase
+
+### 3. Enforce Validator Config Type from Game Config
+
+**Problem:** Easy to forget to add a new setting to validator's `getInitialState()` signature
+
+**Solution:** Make validator use the shared config type
+
+```typescript
+// src/lib/arcade/validation/MemoryQuizGameValidator.ts
+
+import type { MemoryQuizGameConfig } from '@/lib/arcade/game-configs'
+
+export class MemoryQuizGameValidator {
+  // BEFORE: Manual type definition
+  // getInitialState(config: {
+  //   selectedCount: number
+  //   displayTime: number
+  //   selectedDifficulty: DifficultyLevel
+  //   playMode?: 'cooperative' | 'competitive'
+  // }): SorobanQuizState
+
+  // AFTER: Use shared type
+  getInitialState(config: MemoryQuizGameConfig): SorobanQuizState {
+    return {
+      // ...
+      selectedCount: config.selectedCount,
+      displayTime: config.displayTime,
+      selectedDifficulty: config.selectedDifficulty,
+      playMode: config.playMode,  // TypeScript ensures all fields are handled
+      // ...
+    }
+  }
+}
+```
+
+**Benefits:**
+- If you add a setting to `MemoryQuizGameConfig`, TypeScript forces you to handle it
+- Impossible to forget a setting
+- Impossible to use wrong type
+
+### 4. Add Exhaustiveness Checking
+
+**Problem:** Easy to miss handling a setting field
+
+**Solution:** Use TypeScript's exhaustiveness checking
+
+```typescript
+// src/lib/arcade/validation/MemoryQuizGameValidator.ts
+
+getInitialState(config: MemoryQuizGameConfig): SorobanQuizState {
+  // Exhaustiveness check - ensures all config fields are used
+  const _exhaustivenessCheck: Record<keyof MemoryQuizGameConfig, boolean> = {
+    selectedCount: true,
+    displayTime: true,
+    selectedDifficulty: true,
+    playMode: true,
+  }
+
+  return {
+    // ... use all config fields
+    selectedCount: config.selectedCount,
+    displayTime: config.displayTime,
+    selectedDifficulty: config.selectedDifficulty,
+    playMode: config.playMode,
+  }
+}
+```
+
+If you add a new field to `MemoryQuizGameConfig`, TypeScript will error on `_exhaustivenessCheck` until you add it.
+
+### 5. Validate Config on Save
+
+**Problem:** Invalid config can be saved to database
+
+**Solution:** Add runtime validation
+
+```typescript
+// src/lib/arcade/game-config-helpers.ts
+
+export function validateGameConfig(
+  gameName: GameName,
+  config: any
+): config is MatchingGameConfig | MemoryQuizGameConfig {
+  switch (gameName) {
+    case 'matching':
+      return (
+        typeof config.gameType === 'string' &&
+        ['abacus-numeral', 'complement-pairs'].includes(config.gameType) &&
+        typeof config.difficulty === 'number' &&
+        config.difficulty > 0 &&
+        typeof config.turnTimer === 'number' &&
+        config.turnTimer > 0
+      )
+
+    case 'memory-quiz':
+      return (
+        [2, 5, 8, 12, 15].includes(config.selectedCount) &&
+        typeof config.displayTime === 'number' &&
+        config.displayTime > 0 &&
+        ['beginner', 'easy', 'medium', 'hard', 'expert'].includes(config.selectedDifficulty) &&
+        ['cooperative', 'competitive'].includes(config.playMode)
+      )
+
+    default:
+      return false
+  }
+}
+```
+
+Use in settings API:
+```typescript
+// src/app/api/arcade/rooms/[roomId]/settings/route.ts
+
+if (body.gameConfig !== undefined) {
+  if (!validateGameConfig(room.gameName, body.gameConfig[room.gameName])) {
+    return NextResponse.json({ error: 'Invalid game config' }, { status: 400 })
+  }
+  updateData.gameConfig = body.gameConfig
+}
+```
+
+## Schema Refactoring: Separate Table for Game Configs
+
+### Current Problem
+
+All game configs are stored in a single JSON column in `arcade_rooms.gameConfig`:
+
+```json
+{
+  "matching": { "gameType": "...", "difficulty": 15 },
+  "memory-quiz": { "selectedCount": 8, "playMode": "competitive" }
+}
+```
+
+**Issues:**
+- No schema validation
+- Inefficient updates (read/parse/modify/serialize entire blob)
+- Grows without bounds as more games added
+- Can't query or index individual game settings
+- No audit trail
+- Potential concurrent update race conditions
+
+### Recommended: Separate Table
+
+Create `room_game_configs` table with one row per game per room:
+
+```typescript
+// src/db/schema/room-game-configs.ts
+
+export const roomGameConfigs = sqliteTable('room_game_configs', {
+  id: text('id').primaryKey().$defaultFn(() => createId()),
+  roomId: text('room_id')
+    .notNull()
+    .references(() => arcadeRooms.id, { onDelete: 'cascade' }),
+  gameName: text('game_name', {
+    enum: ['matching', 'memory-quiz', 'complement-race'],
+  }).notNull(),
+  config: text('config', { mode: 'json' }).notNull(), // Game-specific JSON
+  createdAt: integer('created_at', { mode: 'timestamp' })
+    .notNull()
+    .$defaultFn(() => new Date()),
+  updatedAt: integer('updated_at', { mode: 'timestamp' })
+    .notNull()
+    .$defaultFn(() => new Date()),
+}, (table) => ({
+  uniqueRoomGame: uniqueIndex('room_game_idx').on(table.roomId, table.gameName),
+}))
+```
+
+**Benefits:**
+- ✅ Smaller rows (only configs for games that have been used)
+- ✅ Easier updates (single row, not entire JSON blob)
+- ✅ Can track updatedAt per game
+- ✅ Better concurrency (no lock contention between games)
+- ✅ Foundation for future audit trail
+
+**Migration Strategy:**
+1. Create new table
+2. Migrate existing data from `arcade_rooms.gameConfig`
+3. Update all config read/write code
+4. Deploy and test
+5. Drop old `gameConfig` column from `arcade_rooms`
+
+See migration SQL below.
+
+## Implementation Priority
+
+### Phase 1: Schema Migration (HIGHEST PRIORITY)
+1. **Create new table** - Add `room_game_configs` schema
+2. **Create migration** - SQL to migrate existing data
+3. **Update helper functions** - Adapt to new table structure
+4. **Update all read/write code** - Use new table
+5. **Test thoroughly** - Verify all settings persist correctly
+6. **Drop old column** - Remove `gameConfig` from `arcade_rooms`
+
+### Phase 2: Type Safety (HIGH)
+1. **Create shared config types** (`game-configs.ts`) - Prevents type mismatches
+2. **Create helper functions** (`game-config-helpers.ts`) - Now queries new table
+3. **Update validators** to use shared types - Enforces consistency
+
+### Phase 3: Compile-Time Safety (MEDIUM)
+1. **Add exhaustiveness checking** - Catches missing fields at compile time
+2. **Enforce validator config types** - Use shared types
+
+### Phase 4: Runtime Safety (LOW)
+1. **Add runtime validation** - Prevents invalid data from being saved
+
+## Detailed Migration SQL
+
+```sql
+-- drizzle/migrations/XXXX_split_game_configs.sql
+
+-- Create new table
+CREATE TABLE room_game_configs (
+  id TEXT PRIMARY KEY,
+  room_id TEXT NOT NULL REFERENCES arcade_rooms(id) ON DELETE CASCADE,
+  game_name TEXT NOT NULL CHECK(game_name IN ('matching', 'memory-quiz', 'complement-race')),
+  config TEXT NOT NULL,  -- JSON
+  created_at INTEGER NOT NULL,
+  updated_at INTEGER NOT NULL
+);
+
+CREATE UNIQUE INDEX room_game_idx ON room_game_configs(room_id, game_name);
+
+-- Migrate existing 'matching' configs
+INSERT INTO room_game_configs (id, room_id, game_name, config, created_at, updated_at)
+SELECT
+  lower(hex(randomblob(16))),
+  id,
+  'matching',
+  json_extract(game_config, '$.matching'),
+  created_at,
+  last_activity
+FROM arcade_rooms
+WHERE json_extract(game_config, '$.matching') IS NOT NULL;
+
+-- Migrate existing 'memory-quiz' configs
+INSERT INTO room_game_configs (id, room_id, game_name, config, created_at, updated_at)
+SELECT
+  lower(hex(randomblob(16))),
+  id,
+  'memory-quiz',
+  json_extract(game_config, '$."memory-quiz"'),
+  created_at,
+  last_activity
+FROM arcade_rooms
+WHERE json_extract(game_config, '$."memory-quiz"') IS NOT NULL;
+
+-- After testing and verifying all works:
+-- ALTER TABLE arcade_rooms DROP COLUMN game_config;
+```
+
+## Migration Strategy
+
+### Step-by-Step with Checkpoints
+
+**Checkpoint 1: Schema & Migration**
+1. Create `src/db/schema/room-game-configs.ts`
+2. Export from `src/db/schema/index.ts`
+3. Generate and apply migration
+4. Verify data migrated correctly
+
+**Checkpoint 2: Helper Functions**
+1. Create shared config types in `src/lib/arcade/game-configs.ts`
+2. Create helper functions in `src/lib/arcade/game-config-helpers.ts`
+3. Add unit tests for helpers
+
+**Checkpoint 3: Update Config Reads**
+1. Update socket-server.ts to read from new table
+2. Update RoomMemoryQuizProvider to read from new table
+3. Update RoomMemoryPairsProvider to read from new table
+4. Test: Load room and verify settings appear
+
+**Checkpoint 4: Update Config Writes**
+1. Update useRoomData.ts updateGameConfig to write to new table
+2. Update settings API to write to new table
+3. Test: Change settings and verify they persist
+
+**Checkpoint 5: Update Validators**
+1. Update validators to use shared config types
+2. Test: All games work correctly
+
+**Checkpoint 6: Cleanup**
+1. Remove old gameConfig column references
+2. Drop gameConfig column from arcade_rooms table
+3. Final testing of all games
+
+## Benefits Summary
+
+- **Type Safety:** TypeScript enforces consistency across all systems
+- **DRY:** Config reading logic not duplicated
+- **Maintainability:** Adding a setting requires changes in fewer places
+- **Correctness:** Impossible to forget a setting or use wrong type
+- **Debugging:** Centralized config logic easier to trace
+- **Testing:** Can test config helpers in isolation

apps/web/.claude/MANUAL_MIGRATION_0011.md

@@ -0,0 +1,120 @@
+# Manual Migration: room_game_configs Table
+
+**Date:** 2025-10-15
+**Migration:** Create `room_game_configs` table (equivalent to drizzle migration 0011)
+
+## Context
+
+This migration was applied manually using sqlite3 CLI instead of through drizzle-kit's migration system, because the interactive prompt from `drizzle-kit push` cannot be automated in the deployment pipeline.
+
+## What Was Done
+
+### 1. Created Table
+
+```sql
+CREATE TABLE IF NOT EXISTS room_game_configs (
+  id TEXT PRIMARY KEY NOT NULL,
+  room_id TEXT NOT NULL,
+  game_name TEXT NOT NULL,
+  config TEXT NOT NULL,
+  created_at INTEGER NOT NULL,
+  updated_at INTEGER NOT NULL,
+  FOREIGN KEY (room_id) REFERENCES arcade_rooms(id) ON UPDATE NO ACTION ON DELETE CASCADE
+);
+```
+
+### 2. Created Index
+
+```sql
+CREATE UNIQUE INDEX IF NOT EXISTS room_game_idx ON room_game_configs (room_id, game_name);
+```
+
+### 3. Migrated Existing Data
+
+Migrated 6000 game configs from the old `arcade_rooms.game_config` column to the new normalized table:
+
+```sql
+INSERT OR IGNORE INTO room_game_configs (id, room_id, game_name, config, created_at, updated_at)
+SELECT
+  lower(hex(randomblob(16))) as id,
+  id as room_id,
+  game_name,
+  game_config as config,
+  created_at,
+  last_activity as updated_at
+FROM arcade_rooms
+WHERE game_config IS NOT NULL
+  AND game_name IS NOT NULL;
+```
+
+**Results:**
+- 5991 matching game configs migrated
+- 9 memory-quiz game configs migrated
+- Total: 6000 configs
+
+## Old vs New Schema
+
+**Old Schema:**
+- `arcade_rooms.game_config` (TEXT/JSON) - stored config for currently selected game only
+- Config was lost when switching games
+
+**New Schema:**
+- `room_game_configs` table - one row per game per room
+- Unique constraint on (room_id, game_name)
+- Configs persist when switching between games
+
+## Verification
+
+```bash
+# Verify table exists
+sqlite3 data/sqlite.db ".tables" | grep room_game_configs
+
+# Verify schema
+sqlite3 data/sqlite.db ".schema room_game_configs"
+
+# Count migrated data
+sqlite3 data/sqlite.db "SELECT COUNT(*) FROM room_game_configs;"
+# Expected: 6000
+
+# Check data distribution
+sqlite3 data/sqlite.db "SELECT game_name, COUNT(*) FROM room_game_configs GROUP BY game_name;"
+# Expected: matching: 5991, memory-quiz: 9
+```
+
+## Related Files
+
+This migration supports the refactoring documented in:
+- `.claude/GAME_SETTINGS_PERSISTENCE.md` - Architecture documentation
+- `src/lib/arcade/game-configs.ts` - Shared config types
+- `src/lib/arcade/game-config-helpers.ts` - Database access helpers
+
+## Note on Drizzle Migration Tracking
+
+This migration was NOT recorded in drizzle's `__drizzle_migrations` table because it was applied manually. This is acceptable because:
+
+1. The schema definition exists in code (`src/db/schema/room-game-configs.ts`)
+2. The table was created with the exact schema drizzle would generate
+3. Future schema changes will go through proper drizzle migrations
+4. The `arcade_rooms.game_config` column is preserved for rollback safety
+
+## Rollback Plan
+
+If issues arise, the old system can be restored by:
+
+1. Reverting code changes (game-config-helpers.ts, API routes, validators)
+2. The old `game_config` column still exists in `arcade_rooms` table
+3. Data is still there (we only read from it, didn't delete it)
+
+The new `room_game_configs` table can be dropped if needed:
+
+```sql
+DROP TABLE IF EXISTS room_game_configs;
+```
+
+## Future Work
+
+Once this migration is stable in production:
+
+1. Consider dropping the old `arcade_rooms.game_config` column
+2. Add this migration to drizzle's migration journal for tracking (optional)
+3. Monitor for any issues with settings persistence

apps/web/.claude/settings.local.json

@@ -70,7 +70,15 @@
       "Bash(lsof:*)",
       "Bash(killall:*)",
       "Bash(echo:*)",
-      "Bash(git restore:*)"
+      "Bash(git restore:*)",
+      "Bash(timeout 10 npm run dev:*)",
+      "Bash(timeout 30 npm run dev)",
+      "Bash(pkill:*)",
+      "Bash(for i in {1..30})",
+      "Bash(do gh run list --limit 1 --json conclusion,status,name,databaseId --jq '.[0] | \"\"\\(.status) - \\(.conclusion // \"\"running\"\") - Run ID: \\(.databaseId)\"\"')",
+      "Bash(tsc:*)",
+      "Bash(tsc-alias:*)",
+      "Bash(npx tsc-alias:*)"
     ],
     "deny": [],
     "ask": []

apps/web/docs/AUDIT_2_ARCHITECTURE_QUALITY.md

@@ -0,0 +1,451 @@
+# Architecture Quality Audit #2
+
+**Date**: 2025-10-16
+**Context**: After implementing Number Guesser (turn-based) and starting Math Sprint (free-for-all)
+**Goal**: Assess if the system is truly modular or if there's too much boilerplate
+
+---
+
+## Executive Summary
+
+**Status**: ⚠️ **Good Foundation, But Boilerplate Issues**
+
+The unified validator registry successfully solved the dual registration problem. However, implementing a second game revealed **significant boilerplate** and **database schema coupling** that violate the modular architecture goals.
+
+**Grade**: **B-** (Down from B+ after implementation testing)
+
+---
+
+## Issues Found
+
+### 🚨 Issue #1: Database Schema Coupling (CRITICAL)
+
+**Problem**: The `room_game_configs` table schema hard-codes game names, preventing true modularity.
+
+**Evidence**:
+```typescript
+// db/schema/room-game-configs.ts
+gameName: text('game_name').$type<'matching' | 'memory-quiz' | 'number-guesser' | 'complement-race'>()
+```
+
+When adding 'math-sprint':
+```
+Type '"math-sprint"' is not assignable to type '"matching" | "memory-quiz" | "number-guesser" | "complement-race"'
+```
+
+**Impact**:
+- ❌ Must manually update database schema for every new game
+- ❌ TypeScript errors force schema migration
+- ❌ Breaks "just register and go" promise
+- ❌ Requires database migration for each game
+
+**Root Cause**: The schema uses a union type instead of a string with runtime validation.
+
+**Fix Required**: Change schema to accept any string, validate against registry at runtime.
+
+---
+
+### ⚠️ Issue #2: game-config-helpers.ts Boilerplate
+
+**Problem**: Three switch statements must be updated for every new game:
+
+1. `getDefaultGameConfig()` - add case
+2. Import default config constant
+3. `validateGameConfig()` - add validation logic
+
+**Example** (from Math Sprint):
+```typescript
+// Must add to imports
+import { DEFAULT_MATH_SPRINT_CONFIG } from './game-configs'
+
+// Must add case to switch #1
+case 'math-sprint':
+  return DEFAULT_MATH_SPRINT_CONFIG
+
+// Must add case to switch #2
+case 'math-sprint':
+  return (
+    typeof config === 'object' &&
+    config !== null &&
+    ['easy', 'medium', 'hard'].includes(config.difficulty) &&
+    // ... 10+ lines of validation
+  )
+```
+
+**Impact**:
+- ⏱️ 5-10 minutes of boilerplate per game
+- 🐛 Easy to forget a switch case
+- 📝 Repetitive validation logic
+
+**Better Approach**: Config defaults and validation should be part of the game definition.
+
+---
+
+### ⚠️ Issue #3: game-configs.ts Boilerplate
+
+**Problem**: Must update 4 places in game-configs.ts:
+
+1. Import types from game
+2. Define `XGameConfig` interface
+3. Add to `GameConfigByName` union
+4. Add to `RoomGameConfig` interface
+5. Create `DEFAULT_X_CONFIG` constant
+
+**Example** (from Math Sprint):
+```typescript
+// 1. Import
+import type { Difficulty as MathSprintDifficulty } from '@/arcade-games/math-sprint/types'
+
+// 2. Interface
+export interface MathSprintGameConfig {
+  difficulty: MathSprintDifficulty
+  questionsPerRound: number
+  timePerQuestion: number
+}
+
+// 3. Add to union
+export type GameConfigByName = {
+  'math-sprint': MathSprintGameConfig
+  // ...
+}
+
+// 4. Add to RoomGameConfig
+export interface RoomGameConfig {
+  'math-sprint'?: MathSprintGameConfig
+  // ...
+}
+
+// 5. Default constant
+export const DEFAULT_MATH_SPRINT_CONFIG: MathSprintGameConfig = {
+  difficulty: 'medium',
+  questionsPerRound: 10,
+  timePerQuestion: 30,
+}
+```
+
+**Impact**:
+- ⏱️ 10-15 lines of boilerplate per game
+- 🐛 Easy to forget one of the 5 updates
+- 🔄 Repeating type information (already in game definition)
+
+**Better Approach**: Game config types should be inferred from game definitions.
+
+---
+
+### 📊 Issue #4: High Boilerplate Ratio
+
+**Files Required Per Game**:
+
+| Category | Files | Purpose |
+|----------|-------|---------|
+| **Game Code** | 7 files | types.ts, Validator.ts, Provider.tsx, index.ts, 3x components |
+| **Registration** | 2 files | validators.ts, game-registry.ts |
+| **Config** | 2 files | game-configs.ts, game-config-helpers.ts |
+| **Database** | 1 file | schema migration |
+| **Total** | **12 files** | For one game! |
+
+**Lines of Boilerplate** (non-game-logic):
+- game-configs.ts: ~15 lines
+- game-config-helpers.ts: ~25 lines
+- validators.ts: ~2 lines
+- game-registry.ts: ~2 lines
+- **Total: ~44 lines of pure boilerplate per game**
+
+**Comparison**:
+- Number Guesser: ~500 lines of actual game logic
+- Boilerplate: ~44 lines (8.8% overhead) ✅ Acceptable
+- But spread across 4 different files ⚠️ Developer friction
+
+---
+
+## Positive Aspects
+
+### ✅ What Works Well
+
+1. **SDK Abstraction**
+   - `useArcadeSession` is clean and reusable
+   - `buildPlayerMetadata` helper reduces duplication
+   - Hook-based API is intuitive
+
+2. **Provider Pattern**
+   - Consistent across games
+   - Clear separation of concerns
+   - Easy to understand
+
+3. **Component Structure**
+   - SetupPhase, PlayingPhase, ResultsPhase pattern is clear
+   - GameComponent wrapper is simple
+   - PageWithNav integration is seamless
+
+4. **Unified Validator Registry**
+   - Single source of truth for validators ✅
+   - Auto-derived GameName type ✅
+   - Type-safe validator access ✅
+
+5. **Error Feedback**
+   - lastError/clearError pattern works well
+   - Auto-dismiss UX is good
+   - Consistent error handling
+
+---
+
+## Comparison: Number Guesser vs. Math Sprint
+
+### Similarities (Good!)
+- ✅ Same file structure
+- ✅ Same SDK usage patterns
+- ✅ Same Provider pattern
+- ✅ Same component phases
+
+### Differences (Revealing!)
+- Math Sprint uses TEAM_MOVE (no turn owner)
+- Math Sprint has server-generated questions
+- Database schema didn't support Math Sprint name
+
+**Key Insight**: The SDK handles different game types well (turn-based vs. free-for-all), but infrastructure (database, config system) is rigid.
+
+---
+
+## Developer Experience Score
+
+### Time to Add a Game
+
+| Task | Time | Notes |
+|------|------|-------|
+| Write game logic | 2-4 hours | Validator, state management, components |
+| Registration boilerplate | 15-20 min | 4 files to update |
+| Database migration | 10-15 min | Schema update, migration file |
+| Debugging type errors | 10-30 min | Database schema mismatches |
+| **Total** | **3-5 hours** | For a simple game |
+
+### Pain Points
+
+1. **Database Schema** ⚠️ Critical blocker
+   - Must update schema for each game
+   - Requires migration
+   - TypeScript errors are confusing
+
+2. **Config System** ⚠️ Medium friction
+   - 5 places to update in game-configs.ts
+   - Easy to miss one
+   - Repetitive type definitions
+
+3. **Helper Functions** ⚠️ Low friction
+   - Switch statements in game-config-helpers.ts
+   - Not hard, just tedious
+
+### What Developers Like
+
+1. ✅ SDK is intuitive
+2. ✅ Pattern is consistent
+3. ✅ Error messages are clear (once you know where to look)
+4. ✅ Documentation is comprehensive
+
+---
+
+## Architectural Recommendations
+
+### Critical (Before Adding More Games)
+
+**1. Fix Database Schema Coupling**
+
+**Current**:
+```typescript
+gameName: text('game_name').$type<'matching' | 'memory-quiz' | 'number-guesser' | 'complement-race'>()
+```
+
+**Recommended**:
+```typescript
+// Accept any string, validate at runtime
+gameName: text('game_name').$type<string>().notNull()
+
+// Runtime validation in helper functions
+export function validateGameName(gameName: string): gameName is GameName {
+  return hasValidator(gameName)
+}
+```
+
+**Benefits**:
+- ✅ No schema migration per game
+- ✅ Works with auto-derived GameName
+- ✅ Runtime validation is sufficient
+
+---
+
+**2. Infer Config Types from Game Definitions**
+
+**Current** (manual):
+```typescript
+// In game-configs.ts
+export interface MathSprintGameConfig { ... }
+export const DEFAULT_MATH_SPRINT_CONFIG = { ... }
+
+// In game definition
+const defaultConfig: MathSprintGameConfig = { ... }
+```
+
+**Recommended**:
+```typescript
+// In game definition (single source of truth)
+export const mathSprintGame = defineGame({
+  defaultConfig: {
+    difficulty: 'medium',
+    questionsPerRound: 10,
+    timePerQuestion: 30,
+  },
+  validator: mathSprintValidator,
+  // ...
+})
+
+// Auto-infer types
+type MathSprintConfig = typeof mathSprintGame.defaultConfig
+```
+
+**Benefits**:
+- ✅ No duplication
+- ✅ Single source of truth
+- ✅ Type inference handles it
+
+---
+
+**3. Move Config Validation to Game Definition**
+
+**Current** (switch statement in helper):
+```typescript
+function validateGameConfig(gameName: GameName, config: any): boolean {
+  switch (gameName) {
+    case 'math-sprint':
+      return /* 15 lines of validation */
+  }
+}
+```
+
+**Recommended**:
+```typescript
+// In game definition
+export const mathSprintGame = defineGame({
+  defaultConfig: { ... },
+  validateConfig: (config: any): config is MathSprintConfig => {
+    return /* validation logic */
+  },
+  // ...
+})
+
+// In helper (generic)
+export function validateGameConfig(gameName: GameName, config: any): boolean {
+  const game = getGame(gameName)
+  return game?.validateConfig?.(config) ?? true
+}
+```
+
+**Benefits**:
+- ✅ No switch statement
+- ✅ Validation lives with game
+- ✅ One place to update
+
+---
+
+### Medium Priority
+
+**4. Create CLI Tool for Game Generation**
+
+```bash
+npm run create-game math-sprint "Math Sprint" "🧮"
+```
+
+Generates:
+- File structure
+- Boilerplate code
+- Registration entries
+- Types
+
+**Benefits**:
+- ✅ Eliminates manual boilerplate
+- ✅ Consistent structure
+- ✅ Reduces errors
+
+---
+
+**5. Add Runtime Registry Validation**
+
+On app start, verify:
+- ✅ All games in registry have validators
+- ✅ All validators have games
+- ✅ No orphaned configs
+- ✅ All game names are unique
+
+```typescript
+function validateRegistries() {
+  const games = getAllGames()
+  const validators = getRegisteredGameNames()
+
+  for (const game of games) {
+    if (!validators.includes(game.manifest.name)) {
+      throw new Error(`Game ${game.manifest.name} has no validator!`)
+    }
+  }
+}
+```
+
+---
+
+## Updated Compliance Table
+
+| Intention | Status | Notes |
+|-----------|--------|-------|
+| Modularity | ⚠️ Partial | Validators unified, but database/config not modular |
+| Self-registration | ✅ Pass | Two registration points (validator + game), both clear |
+| Type safety | ⚠️ Partial | Types work, but database schema breaks for new games |
+| No core changes | ⚠️ Partial | Must update 4 files + database schema |
+| Drop-in games | ❌ Fail | Database migration required |
+| Stable SDK API | ✅ Pass | SDK is excellent |
+| Clear patterns | ✅ Pass | Patterns are consistent |
+| Low boilerplate | ⚠️ Partial | SDK usage is clean, registration is verbose |
+
+**Overall Grade**: **B-** (Was B+, downgraded after implementation testing)
+
+---
+
+## Summary
+
+### What We Learned
+
+✅ **The Good**:
+- SDK design is solid
+- Unified validator registry works
+- Pattern is consistent and learnable
+- Number Guesser proves the concept
+
+⚠️ **The Not-So-Good**:
+- Database schema couples to game names (critical blocker)
+- Config system has too much boilerplate
+- 12 files touched per game is high
+
+❌ **The Bad**:
+- Can't truly "drop in" a game without schema migration
+- Config types are duplicated
+- Helper switch statements are tedious
+
+### Verdict
+
+The system **works** and is **usable**, but falls short of "modular architecture" goals due to:
+1. Database schema hard-coding
+2. Config system boilerplate
+3. Required schema migrations
+
+**Recommendation**:
+1. **Option A (Quick Fix)**: Document the 12-file checklist, live with boilerplate for now
+2. **Option B (Proper Fix)**: Implement Critical recommendations 1-3 before adding Math Sprint
+
+**My Recommendation**: Option A for now (get Math Sprint working), then Option B as a refactoring sprint.
+
+---
+
+## Next Steps
+
+1. ✅ Document "Adding a Game" checklist (12 files)
+2. 🔴 Fix database schema to accept any game name
+3. 🟡 Test Math Sprint with current architecture
+4. 🟡 Evaluate if boilerplate is acceptable in practice
+5. 🟢 Consider config system refactoring for later
+

apps/web/docs/AUDIT_MODULAR_GAME_SYSTEM.md

@@ -0,0 +1,519 @@
+# Modular Game System Audit
+
+**Date**: 2025-10-15
+**Updated**: 2025-10-15
+**Status**: ✅ CRITICAL ISSUE RESOLVED
+
+---
+
+## Executive Summary
+
+The modular game system **now meets its stated intentions** after implementing the unified validator registry. The critical dual registration issue has been resolved.
+
+**Original Issue**: Client-side implementation (SDK, registry, game definitions) was well-designed, but server-side validation used a hard-coded legacy system, breaking the core premise of modularity.
+
+**Resolution**: Created unified isomorphic validator registry (`src/lib/arcade/validators.ts`) that serves both client and server needs, with auto-derived GameName type.
+
+**Verdict**: ✅ **Production Ready** - System is now truly modular with single registration point
+
+---
+
+## Intention vs. Reality
+
+### Stated Intentions
+
+> "A modular, plugin-based architecture for building multiplayer arcade games"
+>
+> **Goals:**
+> 1. **Modularity**: Each game is self-contained and independently deployable
+> 2. Games register themselves with a central registry
+> 3. No need to modify core infrastructure when adding games
+
+### Current Reality
+
+✅ **Client-Side**: Fully modular, games use SDK and register themselves
+❌ **Server-Side**: Hard-coded validator map, requires manual code changes
+❌ **Overall**: **System is NOT modular** - adding a game requires editing 2 different registries
+
+---
+
+## Critical Issues
+
+### ✅ Issue #1: Dual Registration System (RESOLVED)
+
+**Original Problem**: Games had to register in TWO separate places:
+
+1. **Client Registry** (`src/lib/arcade/game-registry.ts`)
+2. **Server Validator Map** (`src/lib/arcade/validation/index.ts`)
+
+**Impact**:
+- ❌ Broke modularity - couldn't just drop in a new game
+- ❌ Easy to forget one registration, causing runtime errors
+- ❌ Violated DRY principle
+- ❌ Two sources of truth for "what games exist"
+
+**Resolution** (Implemented 2025-10-15):
+
+Created unified isomorphic validator registry at `src/lib/arcade/validators.ts`:
+
+```typescript
+export const validatorRegistry = {
+  matching: matchingGameValidator,
+  'memory-quiz': memoryQuizGameValidator,
+  'number-guesser': numberGuesserValidator,
+  // Add new games here - GameName type auto-updates!
+} as const
+
+// Auto-derived type - no manual updates needed!
+export type GameName = keyof typeof validatorRegistry
+```
+
+**Changes Made**:
+1. ✅ Created `src/lib/arcade/validators.ts` - Unified validator registry (isomorphic)
+2. ✅ Updated `validation/index.ts` - Now re-exports from unified registry (backwards compatible)
+3. ✅ Updated `validation/types.ts` - GameName now auto-derived (no more hard-coded union)
+4. ✅ Updated `session-manager.ts` - Imports from unified registry
+5. ✅ Updated `socket-server.ts` - Imports from unified registry
+6. ✅ Updated `route.ts` - Uses `hasValidator()` instead of hard-coded array
+7. ✅ Updated `game-config-helpers.ts` - Handles ExtendedGameName for legacy games
+8. ✅ Updated `game-registry.ts` - Added runtime validation check
+
+**Benefits**:
+- ✅ Single registration point for validators
+- ✅ Auto-derived GameName type (no manual updates)
+- ✅ Type-safe validator access
+- ✅ Backwards compatible with existing code
+- ✅ Runtime warnings for registration mismatches
+
+**Commit**: `refactor(arcade): create unified validator registry to fix dual registration` (9459f37b)
+
+---
+
+### ✅ Issue #2: Validators Not Accessible from Registry (RESOLVED)
+
+**Original Problem**: The `GameDefinition` contained validators, but server couldn't access them because `game-registry.ts` imported React components.
+
+**Resolution**: Created separate isomorphic validator registry that server can import without pulling in client-only code.
+
+**How It Works Now**:
+- `src/lib/arcade/validators.ts` - Isomorphic, server can import safely
+- `src/lib/arcade/game-registry.ts` - Client-only, imports React components
+- Both use the same validator instances (verified at runtime)
+
+**Benefits**:
+- ✅ Server has direct access to validators
+- ✅ No need for dual validator maps
+- ✅ Clear separation: validators (isomorphic) vs UI (client-only)
+
+---
+
+### ⚠️ Issue #3: Type System Fragmentation
+
+**Problem**: Multiple overlapping type definitions for same concepts:
+
+**GameValidator** has THREE definitions:
+1. `validation/types.ts` - Legacy validator interface
+2. `game-sdk/types.ts` - SDK validator interface (extends legacy)
+3. Individual game validators - Implement one or both?
+
+**GameMove** has TWO type systems:
+1. `validation/types.ts` - Legacy move types (MatchingFlipCardMove, etc.)
+2. Game-specific types in each game's `types.ts`
+
+**GameName** is hard-coded:
+```typescript
+// validation/types.ts:9
+export type GameName = 'matching' | 'memory-quiz' | 'complement-race' | 'number-guesser'
+```
+
+This must be manually updated for every new game!
+
+**Impact**:
+- Confusing which types to use
+- Easy to use wrong import
+- GameName type doesn't auto-update from registry
+
+---
+
+### ⚠️ Issue #4: Old Games Not Migrated
+
+**Problem**: Existing games (matching, memory-quiz) still use old structure:
+
+**Old Pattern** (matching, memory-quiz):
+```
+src/app/arcade/matching/
+  ├── context/           (Old pattern)
+  │   └── RoomMemoryPairsProvider.tsx
+  └── components/
+```
+
+**New Pattern** (number-guesser):
+```
+src/arcade-games/number-guesser/
+  ├── index.ts           (New pattern)
+  ├── Validator.ts
+  ├── Provider.tsx
+  └── components/
+```
+
+**Impact**:
+- Inconsistent codebase structure
+- Two different patterns developers must understand
+- Documentation shows new pattern, but most games use old pattern
+- Confusing for new developers
+
+**Evidence**:
+- `src/app/arcade/matching/` - Uses old structure
+- `src/app/arcade/memory-quiz/` - Uses old structure
+- `src/arcade-games/number-guesser/` - Uses new structure
+
+---
+
+### ✅ Issue #5: Manual GameName Type Updates (RESOLVED)
+
+**Original Problem**: `GameName` type was a hard-coded union that had to be manually updated for each new game.
+
+**Resolution**: Changed validator registry from Map to const object, enabling type derivation:
+
+```typescript
+// src/lib/arcade/validators.ts
+export const validatorRegistry = {
+  matching: matchingGameValidator,
+  'memory-quiz': memoryQuizGameValidator,
+  'number-guesser': numberGuesserValidator,
+  // Add new games here...
+} as const
+
+// Auto-derived! No manual updates needed!
+export type GameName = keyof typeof validatorRegistry
+```
+
+**Benefits**:
+- ✅ GameName type updates automatically when adding to registry
+- ✅ Impossible to forget type update (it's derived)
+- ✅ Single registration step (just add to validatorRegistry)
+- ✅ Type-safe throughout codebase
+
+---
+
+## Secondary Issues
+
+### Issue #6: No Server-Side Registry Access
+
+**Problem**: Server code cannot import `game-registry.ts` because it contains React components.
+
+**Why**:
+- `GameDefinition` includes `Provider` and `GameComponent` (React components)
+- Server-side code runs in Node.js, can't import React components
+- No way to access just the validator from registry
+
+**Potential Solutions**:
+1. Split registry into isomorphic and client-only parts
+2. Separate validator registration from game registration
+3. Use conditional exports in package.json
+
+---
+
+### Issue #7: Documentation Doesn't Match Reality
+
+**Problem**: Documentation describes a fully modular system, but reality requires manual edits in multiple places.
+
+**From README.md**:
+> "Step 7: Register Game - Add to src/lib/arcade/game-registry.ts"
+
+**Missing Steps**:
+- Also add to `validation/index.ts` validator map
+- Also add to `GameName` type union
+- Import validator in server files
+
+**Impact**: Developers follow docs, game doesn't work, confusion ensues.
+
+---
+
+### Issue #8: No Validation of Registered Games
+
+**Problem**: Registration is type-safe but has no runtime validation:
+
+```typescript
+registerGame(numberGuesserGame)  // No validation that validator works
+```
+
+**Missing Checks**:
+- Does validator implement all required methods?
+- Does manifest match expected schema?
+- Are all required fields present?
+- Does validator.getInitialState() return valid state?
+
+**Impact**: Bugs only caught at runtime when game is played.
+
+---
+
+## Proposed Solutions
+
+### Solution 1: Unified Server-Side Registry (RECOMMENDED)
+
+**Create isomorphic validator registry**:
+
+```typescript
+// src/lib/arcade/validators.ts (NEW FILE - isomorphic)
+import { numberGuesserValidator } from '@/arcade-games/number-guesser/Validator'
+import { matchingGameValidator } from '@/lib/arcade/validation/MatchingGameValidator'
+// ... other validators
+
+export const validatorRegistry = new Map([
+  ['number-guesser', numberGuesserValidator],
+  ['matching', matchingGameValidator],
+  // ...
+])
+
+export function getValidator(gameName: string) {
+  const validator = validatorRegistry.get(gameName)
+  if (!validator) throw new Error(`No validator for game: ${gameName}`)
+  return validator
+}
+
+export type GameName = keyof typeof validatorRegistry  // Auto-derived!
+```
+
+**Update game-registry.ts** to use this:
+
+```typescript
+// src/lib/arcade/game-registry.ts
+import { getValidator } from './validators'
+
+export function registerGame(game: GameDefinition) {
+  const { name } = game.manifest
+
+  // Verify validator is registered server-side
+  const validator = getValidator(name)
+  if (validator !== game.validator) {
+    console.warn(`[Registry] Validator mismatch for ${name}`)
+  }
+
+  registry.set(name, game)
+}
+```
+
+**Pros**:
+- Single source of truth for validators
+- Auto-derived GameName type
+- Client and server use same validator
+- Only one registration needed
+
+**Cons**:
+- Still requires manual import in validators.ts
+- Doesn't solve "drop in a game" fully
+
+---
+
+### Solution 2: Code Generation
+
+**Auto-generate validator registry from file system**:
+
+```typescript
+// scripts/generate-registry.ts
+// Scans src/arcade-games/**/Validator.ts
+// Generates validators.ts and game-registry imports
+```
+
+**Pros**:
+- Truly modular - just add folder, run build
+- No manual registration
+- Auto-derived types
+
+**Cons**:
+- Build-time complexity
+- Magic (harder to understand)
+- May not work with all bundlers
+
+---
+
+### Solution 3: Split GameDefinition
+
+**Separate client and server concerns**:
+
+```typescript
+// Isomorphic (client + server)
+export interface GameValidatorDefinition {
+  name: string
+  validator: GameValidator
+  defaultConfig: GameConfig
+}
+
+// Client-only
+export interface GameUIDefinition {
+  name: string
+  manifest: GameManifest
+  Provider: GameProviderComponent
+  GameComponent: GameComponent
+}
+
+// Combined (client-only)
+export interface GameDefinition extends GameValidatorDefinition, GameUIDefinition {}
+```
+
+**Pros**:
+- Clear separation of concerns
+- Server can import just validator definition
+- Type-safe
+
+**Cons**:
+- More complexity
+- Still requires two registries
+
+---
+
+## Immediate Action Items
+
+### Critical (Do Before Next Game)
+
+1. **✅ Document the dual registration requirement** (COMPLETED)
+   - ✅ Update README with both registration steps
+   - ✅ Add troubleshooting section for "game not found" errors
+   - ✅ Document unified validator registry in Step 7
+
+2. **✅ Unify validator registration** (COMPLETED 2025-10-15)
+   - ✅ Chose Solution 1 (Unified Server-Side Registry)
+   - ✅ Implemented unified registry (src/lib/arcade/validators.ts)
+   - ✅ Updated session-manager.ts and socket-server.ts
+   - ✅ Tested with number-guesser (no TypeScript errors)
+
+3. **✅ Auto-derive GameName type** (COMPLETED 2025-10-15)
+   - ✅ Removed hard-coded union
+   - ✅ Derive from validator registry using `keyof typeof`
+   - ✅ Updated all usages (backwards compatible via re-exports)
+
+### High Priority
+
+4. **🟡 Migrate old games to new pattern**
+   - Move matching to `arcade-games/matching/`
+   - Move memory-quiz to `arcade-games/memory-quiz/`
+   - Update imports and tests
+   - OR document that old games use old pattern (transitional)
+
+5. **🟡 Add validator registration validation**
+   - Runtime check in registerGame()
+   - Warn if validator missing
+   - Validate manifest schema
+
+### Medium Priority
+
+6. **🟢 Clean up type definitions**
+   - Consolidate GameValidator types
+   - Single source of truth for GameMove
+   - Clear documentation on which to use
+
+7. **🟢 Update documentation**
+   - Add "dual registry" warning
+   - Update step-by-step guide
+   - Add troubleshooting for common mistakes
+
+---
+
+## Architectural Debt
+
+### Technical Debt Accumulated
+
+1. **Old validation system** (`validation/types.ts`, `validation/index.ts`)
+   - Used by server-side code
+   - Hard-coded game list
+   - No migration path documented
+
+2. **Mixed game structures** (old in `app/arcade/`, new in `arcade-games/`)
+   - Confusing for developers
+   - Inconsistent imports
+   - Harder to maintain
+
+3. **Type fragmentation** (3 GameValidator definitions)
+   - Unclear which to use
+   - Potential for bugs
+   - Harder to refactor
+
+### Migration Path
+
+**Option A: Big Bang** (Risky)
+- Migrate all games to new structure in one PR
+- Update server to use unified registry
+- High risk of breakage
+
+**Option B: Incremental** (Safer)
+- Document dual registration as "current reality"
+- Create unified validator registry (doesn't break old games)
+- Slowly migrate old games one by one
+- Eventually deprecate old validation system
+
+**Recommendation**: Option B (Incremental)
+
+---
+
+## Compliance with Intentions
+
+| Intention | Status | Notes |
+|-----------|--------|-------|
+| Modularity | ✅ Pass | Single registration in validators.ts + game-registry.ts |
+| Self-registration | ✅ Pass | Both client and server use unified registry |
+| Type safety | ✅ Pass | Good TypeScript coverage + auto-derived GameName |
+| No core changes | ⚠️ Improved | Must edit validators.ts, but one central file |
+| Drop-in games | ⚠️ Improved | Two registration points (validator + game def) |
+| Stable SDK API | ✅ Pass | SDK is well-designed and consistent |
+| Clear patterns | ⚠️ Partial | New pattern is clear, but old games don't follow it |
+
+**Original Grade**: **D** (Failed core modularity requirement)
+**Current Grade**: **B+** (Modularity achieved, some legacy migration pending)
+
+---
+
+## Positive Aspects (What Works Well)
+
+1. **✅ SDK Design** - Clean, well-documented, type-safe
+2. **✅ Client-Side Registry** - Simple, effective pattern
+3. **✅ GameDefinition Structure** - Good separation of concerns
+4. **✅ Documentation** - Comprehensive (though doesn't match reality)
+5. **✅ defineGame() Helper** - Makes game creation easy
+6. **✅ Type Safety** - Excellent TypeScript coverage
+7. **✅ Number Guesser Example** - Good reference implementation
+
+---
+
+## Recommendations
+
+### Immediate (This Sprint)
+
+1. ✅ **Document current reality** - Update docs to show both registrations required
+2. 🔴 **Create unified validator registry** - Implement Solution 1
+3. 🔴 **Update server to use unified registry** - Modify session-manager.ts and socket-server.ts
+
+### Next Sprint
+
+4. 🟡 **Migrate one old game** - Move matching to new structure as proof of concept
+5. 🟡 **Add registration validation** - Runtime checks for validator consistency
+6. 🟡 **Auto-derive GameName** - Remove hard-coded type union
+
+### Future
+
+7. 🟢 **Code generation** - Explore automated registry generation
+8. 🟢 **Plugin system** - True drop-in games with discovery
+9. 🟢 **Deprecate old validation system** - Once all games migrated
+
+---
+
+## Conclusion
+
+The modular game system has a **solid foundation** but is **not truly modular** due to server-side technical debt. The client-side implementation is excellent, but the server still uses a legacy hard-coded validation system.
+
+**Status**: Needs significant refactoring before claiming "modular architecture"
+
+**Path Forward**: Implement unified validator registry (Solution 1), then incrementally migrate old games.
+
+**Risk**: If we add more games before fixing this, technical debt will compound.
+
+---
+
+*This audit was conducted by reviewing:*
+- `src/lib/arcade/game-registry.ts`
+- `src/lib/arcade/validation/index.ts`
+- `src/lib/arcade/session-manager.ts`
+- `src/socket-server.ts`
+- `src/lib/arcade/game-sdk/`
+- `src/arcade-games/number-guesser/`
+- Documentation in `docs/` and `src/arcade-games/README.md`

apps/web/docs/arcade-game-architecture.md

@@ -0,0 +1,792 @@
+# Arcade Game Architecture
+
+> **Design Philosophy**: Modular, type-safe, multiplayer-first game development with real-time synchronization
+
+---
+
+## Table of Contents
+
+- [Design Goals](#design-goals)
+- [Architecture Overview](#architecture-overview)
+- [Core Concepts](#core-concepts)
+- [Implementation Details](#implementation-details)
+- [Design Decisions](#design-decisions)
+- [Lessons Learned](#lessons-learned)
+- [Future Improvements](#future-improvements)
+
+---
+
+## Design Goals
+
+### Primary Goals
+
+1. **Modularity**
+   - Each game is a self-contained module
+   - Games can be added/removed without affecting the core system
+   - No tight coupling between games and infrastructure
+
+2. **Type Safety**
+   - Full TypeScript support throughout the stack
+   - Compile-time validation of game definitions
+   - Type-safe move validation and state management
+
+3. **Multiplayer-First**
+   - Real-time state synchronization via WebSocket
+   - Optimistic updates for instant feedback
+   - Server-authoritative validation to prevent cheating
+
+4. **Developer Experience**
+   - Simple, intuitive API for game creators
+   - Minimal boilerplate
+   - Clear separation of concerns
+   - Comprehensive error messages
+
+5. **Consistency**
+   - Shared navigation and UI components
+   - Standardized player management
+   - Common error handling patterns
+   - Unified room/lobby experience
+
+### Non-Goals
+
+- Supporting non-multiplayer games (use existing game routes for that)
+- Backwards compatibility with old game implementations
+- Supporting games outside the monorepo
+
+---
+
+## Architecture Overview
+
+### System Layers
+
+```
+┌─────────────────────────────────────────────────────────────┐
+│                    Application Layer                         │
+│  - GameSelector (game discovery)                            │
+│  - Room management                                          │
+│  - Player management                                        │
+└─────────────────────────────────────────────────────────────┘
+                            │
+                            ▼
+┌─────────────────────────────────────────────────────────────┐
+│                   Registry Layer                             │
+│  - Game registration                                        │
+│  - Game discovery (getGame, getAllGames)                    │
+│  - Manifest validation                                      │
+└─────────────────────────────────────────────────────────────┘
+                            │
+                            ▼
+┌─────────────────────────────────────────────────────────────┐
+│                      SDK Layer                               │
+│  - Stable API surface                                       │
+│  - React hooks (useArcadeSession, etc.)                     │
+│  - Type definitions                                         │
+│  - Utilities (buildPlayerMetadata, etc.)                    │
+└─────────────────────────────────────────────────────────────┘
+                            │
+                            ▼
+┌─────────────────────────────────────────────────────────────┐
+│                   Game Layer                                 │
+│  Individual games (number-guesser, math-sprint, etc.)      │
+│  Each game: Validator + Provider + Components + Types      │
+└─────────────────────────────────────────────────────────────┘
+                            │
+                            ▼
+┌─────────────────────────────────────────────────────────────┐
+│                Infrastructure Layer                          │
+│  - WebSocket (useArcadeSocket)                              │
+│  - Optimistic state (useOptimisticGameState)                │
+│  - Database (room data, player data)                        │
+└─────────────────────────────────────────────────────────────┘
+```
+
+### Data Flow: Move Execution
+
+```
+1. User clicks button
+   │
+   ▼
+2. Provider calls sendMove()
+   │
+   ▼
+3. useArcadeSession
+   ├─→ Apply optimistically (instant UI update)
+   └─→ Send via WebSocket to server
+   │
+   ▼
+4. Server validates move
+   │
+   ├─→ VALID:
+   │   ├─→ Apply to server state
+   │   ├─→ Increment version
+   │   ├─→ Broadcast to all clients
+   │   └─→ Client: Remove from pending, confirm state
+   │
+   └─→ INVALID:
+       ├─→ Send rejection message
+       └─→ Client: Rollback optimistic state, show error
+```
+
+---
+
+## Core Concepts
+
+### 1. Game Definition
+
+A game is defined by five core pieces:
+
+```typescript
+interface GameDefinition<TConfig, TState, TMove> {
+  manifest: GameManifest          // Display metadata
+  Provider: GameProviderComponent // React context provider
+  GameComponent: GameComponent    // Main UI component
+  validator: GameValidator        // Server validation logic
+  defaultConfig: TConfig          // Default settings
+}
+```
+
+**Why this structure?**
+- `manifest`: Declarative metadata for discovery and UI
+- `Provider`: Encapsulates all game logic and state management
+- `GameComponent`: Pure UI component, no business logic
+- `validator`: Server-authoritative validation prevents cheating
+- `defaultConfig`: Sensible defaults, can be overridden per-room
+
+### 2. Validator (Server-Side)
+
+The validator is the **source of truth** for game logic.
+
+```typescript
+interface GameValidator<TState, TMove> {
+  validateMove(state: TState, move: TMove): ValidationResult
+  isGameComplete(state: TState): boolean
+  getInitialState(config: unknown): TState
+}
+```
+
+**Key Principles:**
+- **Pure functions**: No side effects, no I/O
+- **Deterministic**: Same input → same output
+- **Complete game logic**: All rules enforced here
+- **Returns new state**: Immutable state updates
+
+**Why server-side?**
+- Prevents cheating (client can't fake moves)
+- Single source of truth (no client/server divergence)
+- Easier debugging (all logic in one place)
+- Can add server-only features (analytics, anti-cheat)
+
+### 3. Provider (Client-Side)
+
+The provider manages client state and provides a clean API.
+
+```typescript
+interface GameContextValue {
+  state: GameState           // Current game state
+  lastError: string | null   // Last validation error
+  startGame: () => void      // Action creators
+  makeMove: (data) => void   // ...
+  clearError: () => void
+  exitSession: () => void
+}
+```
+
+**Responsibilities:**
+- Wrap `useArcadeSession` with game-specific actions
+- Build player metadata from game mode context
+- Provide clean, typed API to components
+- Handle room config persistence
+
+**Anti-Pattern:** Don't put game logic here. The provider is a **thin wrapper** around the SDK.
+
+### 4. Optimistic Updates
+
+The system uses **optimistic UI** for instant feedback:
+
+1. User makes a move → UI updates immediately
+2. Move sent to server for validation
+3. Server validates:
+   - ✓ Valid → Confirm optimistic state
+   - ✗ Invalid → Rollback and show error
+
+**Why optimistic updates?**
+- Instant feedback (no perceived latency)
+- Better UX for fast-paced games
+- Handles network issues gracefully
+
+**Tradeoff:**
+- More complex state management
+- Need rollback logic
+- Potential for flashing/jumpy UI on rollback
+
+**When NOT to use:**
+- High-stakes actions (payments, permanent changes)
+- Actions with irreversible side effects
+- When server latency is acceptable
+
+### 5. State Synchronization
+
+State is synchronized across all clients in a room:
+
+```
+Client A makes move → Server validates → Broadcast to all clients
+  ├─→ Client A: Confirm optimistic update
+  ├─→ Client B: Apply server state
+  └─→ Client C: Apply server state
+```
+
+**Conflict Resolution:**
+- Server state is **always authoritative**
+- Version numbers prevent out-of-order updates
+- Pending moves are reapplied after server sync
+
+---
+
+## Implementation Details
+
+### SDK Design
+
+The SDK provides a **stable API surface** that games import from:
+
+```typescript
+// ✅ GOOD: Import from SDK
+import { useArcadeSession, type GameDefinition } from '@/lib/arcade/game-sdk'
+
+// ❌ BAD: Import internal implementation
+import { useArcadeSocket } from '@/hooks/useArcadeSocket'
+```
+
+**Why?**
+- **Stability**: Internal APIs can change, SDK stays stable
+- **Discoverability**: One place to find all game APIs
+- **Encapsulation**: Hide implementation details
+- **Documentation**: SDK is the "public API" to document
+
+**SDK Exports:**
+
+```typescript
+// Types
+export type { GameDefinition, GameValidator, GameState, GameMove, ... }
+
+// React Hooks
+export { useArcadeSession, useRoomData, useGameMode, useViewerId }
+
+// Utilities
+export { defineGame, buildPlayerMetadata, loadManifest }
+```
+
+### Registry Pattern
+
+Games register themselves on module load:
+
+```typescript
+// game-registry.ts
+const registry = new Map<string, GameDefinition>()
+
+export function registerGame(game: GameDefinition) {
+  registry.set(game.manifest.name, game)
+}
+
+export function getGame(name: string) {
+  return registry.get(name)
+}
+
+// At bottom of file
+import { numberGuesserGame } from '@/arcade-games/number-guesser'
+registerGame(numberGuesserGame)
+```
+
+**Why self-registration?**
+- No central "game list" to maintain
+- Games are automatically discovered
+- Import errors are caught at module load time
+- Easy to enable/disable games (comment out registration)
+
+**Alternative Considered:** Auto-discovery via file system
+
+```typescript
+// ❌ Rejected: Magic, fragile, breaks with bundlers
+const games = import.meta.glob('../arcade-games/*/index.ts')
+```
+
+### Player Metadata
+
+Player metadata is built from multiple sources:
+
+```typescript
+function buildPlayerMetadata(
+  playerIds: string[],
+  existingMetadata: Record<string, unknown>,
+  playerMap: Map<string, Player>,
+  viewerId?: string
+): Record<string, PlayerMetadata>
+```
+
+**Sources:**
+1. `playerIds`: Which players are active
+2. `existingMetadata`: Carry over existing data (for reconnects)
+3. `playerMap`: Player details (name, emoji, color, userId)
+4. `viewerId`: Current user (for ownership checks)
+
+**Why so complex?**
+- Players can be local or remote (in rooms)
+- Need to preserve data across state updates
+- Must map player IDs to user IDs for permissions
+- Support for guest players vs. authenticated users
+
+### Move Validation Flow
+
+```typescript
+// 1. Client sends move
+sendMove({
+  type: 'MAKE_GUESS',
+  playerId: 'player-123',
+  userId: 'user-456',
+  timestamp: Date.now(),
+  data: { guess: 42 }
+})
+
+// 2. Optimistic update (client-side)
+const optimisticState = applyMove(currentState, move)
+setOptimisticState(optimisticState)
+
+// 3. Server validates
+const result = validator.validateMove(serverState, move)
+
+// 4a. Valid → Broadcast new state
+if (result.valid) {
+  serverState = result.newState
+  version++
+  broadcastToAllClients({ gameState: serverState, version })
+}
+
+// 4b. Invalid → Send rejection
+else {
+  sendToClient({ error: result.error, move })
+}
+
+// 5. Client handles response
+// Valid: Confirm optimistic state, remove from pending
+// Invalid: Rollback optimistic state, show error
+```
+
+**Key Points:**
+- Optimistic update happens **before** server response
+- Server is **authoritative** (client state can be overwritten)
+- Version numbers prevent stale updates
+- Rejected moves trigger error UI
+
+---
+
+## Design Decisions
+
+### Decision: Server-Authoritative Validation
+
+**Choice:** All game logic runs on server, client is "dumb"
+
+**Rationale:**
+- Prevents cheating (client can't manipulate state)
+- Single source of truth (no client/server divergence)
+- Easier testing (one codebase for game logic)
+- Can add server-side features (analytics, matchmaking)
+
+**Tradeoff:**
+- ➕ Secure, consistent, easier to maintain
+- ➖ Network latency affects UX (mitigated by optimistic updates)
+- ➖ Can't play offline
+
+**Alternative Considered:** Client-side validation + server verification
+- Rejected: Duplicate logic, potential for divergence
+
+### Decision: Optimistic Updates
+
+**Choice:** Apply moves immediately, rollback on rejection
+
+**Rationale:**
+- Instant feedback (no perceived latency)
+- Better UX for turn-based games
+- Handles network issues gracefully
+
+**Tradeoff:**
+- ➕ Feels instant, smooth UX
+- ➖ More complex state management
+- ➖ Potential for jarring rollbacks
+
+**When to disable:** High-stakes actions (payments, permanent bans)
+
+### Decision: TypeScript Everywhere
+
+**Choice:** Full TypeScript on client and server
+
+**Rationale:**
+- Compile-time validation catches bugs early
+- Better IDE support (autocomplete, refactoring)
+- Self-documenting code (types as documentation)
+- Easier refactoring (compiler catches breakages)
+
+**Tradeoff:**
+- ➕ Fewer runtime errors, better DX
+- ➖ Slower initial development (must define types)
+- ➖ Learning curve for new developers
+
+**Alternative Considered:** JavaScript with JSDoc
+- Rejected: JSDoc is not type-safe, easy to drift
+
+### Decision: React Context for State
+
+**Choice:** Each game has a Provider that wraps game logic
+
+**Rationale:**
+- Natural React pattern
+- Easy to compose (Provider wraps GameComponent)
+- No prop drilling
+- Easy to test (can provide mock context)
+
+**Tradeoff:**
+- ➕ Clean component APIs, easy to understand
+- ➖ Can't use context outside React tree
+- ➖ Re-renders if not memoized carefully
+
+**Alternative Considered:** Zustand/Redux
+- Rejected: Overkill for game-specific state, harder to isolate per-game
+
+### Decision: Phase-Based UI
+
+**Choice:** Each game has distinct phases (setup, playing, results)
+
+**Rationale:**
+- Clear separation of concerns
+- Easy to understand game flow
+- Each phase is independently testable
+- Natural mapping to game states
+
+**Tradeoff:**
+- ➕ Organized, predictable
+- ➖ Some duplication (multiple components)
+- ➖ Can't have overlapping phases
+
+**Pattern:**
+
+```typescript
+{state.gamePhase === 'setup' && <SetupPhase />}
+{state.gamePhase === 'playing' && <PlayingPhase />}
+{state.gamePhase === 'results' && <ResultsPhase />}
+```
+
+### Decision: Player Order from Set Iteration
+
+**Choice:** Don't sort player arrays, use Set iteration order
+
+**Rationale:**
+- Set order is consistent within a session
+- Matches UI display order (PageWithNav uses same Set)
+- Avoids alphabetical bias (first player isn't always "AAA")
+
+**Tradeoff:**
+- ➕ UI and game logic always match
+- ➖ Order is not predictable across sessions
+- ➖ Different players see different orders (based on join time)
+
+**Why not sort?**
+- Creates mismatch: UI shows Set order, game uses sorted order
+- Causes "skipping first player" bug (discovered in Number Guesser)
+
+### Decision: No Optimistic Logic in Provider
+
+**Choice:** Provider's `applyMove` just returns current state
+
+```typescript
+const { state, sendMove } = useArcadeSession({
+  applyMove: (state, move) => state // Don't apply, wait for server
+})
+```
+
+**Rationale:**
+- Keeps client logic minimal (less code to maintain)
+- Prevents client/server logic divergence
+- Server is authoritative (no client-side cheats)
+
+**Tradeoff:**
+- ➕ Simple, secure
+- ➖ Slightly slower UX (wait for server)
+
+**When to use client-side `applyMove`:**
+- Very fast-paced games (60fps animations)
+- Purely cosmetic updates (particles, sounds)
+- Never for game logic (scoring, winning, etc.)
+
+---
+
+## Lessons Learned
+
+### From Number Guesser Implementation
+
+#### 1. Type Coercion is Critical
+
+**Problem:** WebSocket/JSON serialization converts numbers to strings.
+
+```typescript
+// Client sends
+sendMove({ data: { guess: 42 } })
+
+// Server receives
+move.data.guess === "42" // String! 😱
+```
+
+**Solution:** Explicit coercion in validator
+
+```typescript
+validateMove(state, move) {
+  case 'MAKE_GUESS':
+    return this.validateGuess(state, Number(move.data.guess))
+}
+```
+
+**Lesson:** Always coerce types from `move.data` in validator.
+
+**Symptom Observed:** User reported "first guess always rejected, second guess always correct" which was caused by:
+- First guess: `"42" < 1` evaluates to `false` (string comparison)
+- Validator thinks it's valid, calculates distance as `NaN`
+- `NaN === 0` is false, so guess is "wrong"
+- Second guess: `"50" < 1` also evaluates oddly, but `Math.abs("50" - 42)` coerces correctly
+- The behavior was unpredictable due to mixed type coercion
+
+**Root Cause:** String comparison operators (`<`, `>`) have weird behavior with string numbers.
+
+#### 2. Player Ordering Must Be Consistent
+
+**Problem:** Set iteration order differed from sorted order, causing "skipped player" bug.
+
+**Root Cause:**
+- UI used `Array.from(Set)` → Set iteration order
+- Game used `Array.from(Set).sort()` → Alphabetical order
+- Leftmost UI player ≠ First game player
+
+**Solution:** Remove `.sort()` everywhere, use raw Set order.
+
+**Lesson:** Player order must be identical in UI and game logic.
+
+#### 3. Error Feedback is Essential
+
+**Problem:** Moves rejected silently, users confused.
+
+**Solution:** `lastError` state with auto-dismiss UI.
+
+```typescript
+const { lastError, clearError } = useArcadeSession()
+
+{lastError && (
+  <ErrorBanner message={lastError} onDismiss={clearError} />
+)}
+```
+
+**Lesson:** Always surface validation errors to users.
+
+#### 4. Turn Indicators Improve UX
+
+**Problem:** Players didn't know whose turn it was.
+
+**Solution:** `currentPlayerId` prop to `PageWithNav`.
+
+```typescript
+<PageWithNav
+  currentPlayerId={state.currentPlayer}
+  playerScores={state.scores}
+>
+```
+
+**Lesson:** Visual feedback for turn-based games is critical.
+
+#### 5. Round vs. Game Completion
+
+**Problem:** Validator checked `!state.winner` for next round, but winner is only set when game ends.
+
+**Root Cause:** Confused "round complete" (someone guessed) with "game complete" (someone won).
+
+**Solution:** Check if last guess was correct:
+
+```typescript
+const roundComplete = state.guesses.length > 0 &&
+  state.guesses[state.guesses.length - 1].distance === 0
+```
+
+**Lesson:** Be precise about what "complete" means (round vs. game).
+
+#### 6. Debug Logging is Invaluable
+
+**Problem:** Type issues caused subtle bugs (always correct guess).
+
+**Solution:** Add logging in validator:
+
+```typescript
+console.log('[NumberGuesser] Validating guess:', {
+  guess,
+  guessType: typeof guess,
+  secretNumber: state.secretNumber,
+  secretNumberType: typeof state.secretNumber,
+  distance: Math.abs(guess - state.secretNumber)
+})
+```
+
+**Lesson:** Log types and values during development.
+
+---
+
+## Future Improvements
+
+### 1. Automated Testing
+
+**Current State:** Manual testing only
+
+**Proposal:**
+- Unit tests for validators (pure functions, easy to test)
+- Integration tests for Provider + useArcadeSession
+- E2E tests for full game flows (Playwright)
+
+**Example:**
+
+```typescript
+describe('NumberGuesserValidator', () => {
+  it('should reject out-of-bounds guess', () => {
+    const validator = new NumberGuesserValidator()
+    const state = { minNumber: 1, maxNumber: 100, ... }
+    const move = { type: 'MAKE_GUESS', data: { guess: 200 } }
+
+    const result = validator.validateMove(state, move)
+
+    expect(result.valid).toBe(false)
+    expect(result.error).toContain('must be between')
+  })
+})
+```
+
+### 2. Move History / Replay
+
+**Current State:** No move history
+
+**Proposal:**
+- Store all moves in database
+- Allow "replay" of games
+- Enable undo/redo (for certain games)
+- Analytics on player behavior
+
+**Schema:**
+
+```typescript
+interface GameSession {
+  id: string
+  roomId: string
+  gameType: string
+  moves: GameMove[]
+  finalState: GameState
+  startTime: number
+  endTime: number
+}
+```
+
+### 3. Game Analytics
+
+**Current State:** No analytics
+
+**Proposal:**
+- Track game completions, durations, winners
+- Player skill ratings (Elo, TrueSkill)
+- Popular games dashboard
+- A/B testing for game variants
+
+### 4. Spectator Mode
+
+**Current State:** Only active players can view game
+
+**Proposal:**
+- Allow non-players to watch
+- Spectators can't send moves (read-only)
+- Show spectator count in room
+
+**Implementation:**
+
+```typescript
+interface RoomMember {
+  userId: string
+  role: 'player' | 'spectator' | 'host'
+}
+```
+
+### 5. Game Variants
+
+**Current State:** One config per game
+
+**Proposal:**
+- Preset variants (Easy, Medium, Hard)
+- Custom rules per room
+- "House rules" feature
+
+**Example:**
+
+```typescript
+const variants = {
+  beginner: { minNumber: 1, maxNumber: 20, roundsToWin: 1 },
+  standard: { minNumber: 1, maxNumber: 100, roundsToWin: 3 },
+  expert: { minNumber: 1, maxNumber: 1000, roundsToWin: 5 },
+}
+```
+
+### 6. Tournaments / Brackets
+
+**Current State:** Single-room games only
+
+**Proposal:**
+- Multi-round tournaments
+- Bracket generation
+- Leaderboards
+
+### 7. Game Mod Support
+
+**Current State:** Games are hard-coded
+
+**Proposal:**
+- Load games from external bundles
+- Community-created games
+- Sandboxed execution (Deno, WASM)
+
+**Challenges:**
+- Security (untrusted code)
+- Type safety (dynamic loading)
+- Versioning (breaking changes)
+
+### 8. Voice/Video Chat
+
+**Current State:** Text chat only (if implemented)
+
+**Proposal:**
+- WebRTC voice/video
+- Per-room channels
+- Mute/kick controls
+
+---
+
+## Appendix: Key Files Reference
+
+| Path | Purpose |
+|------|---------|
+| `src/lib/arcade/game-sdk/index.ts` | SDK exports (public API) |
+| `src/lib/arcade/game-registry.ts` | Game registration |
+| `src/lib/arcade/manifest-schema.ts` | Manifest validation |
+| `src/hooks/useArcadeSession.ts` | Session management hook |
+| `src/hooks/useArcadeSocket.ts` | WebSocket connection |
+| `src/hooks/useOptimisticGameState.ts` | Optimistic state management |
+| `src/contexts/GameModeContext.tsx` | Player management |
+| `src/components/PageWithNav.tsx` | Game navigation wrapper |
+| `src/arcade-games/number-guesser/` | Example game implementation |
+
+---
+
+## Related Documentation
+
+- [Game Development Guide](../arcade-games/README.md) - Step-by-step guide to creating games
+- [API Reference](./arcade-game-api-reference.md) - Complete SDK API documentation (TODO)
+- [Deployment Guide](./arcade-game-deployment.md) - How to deploy new games (TODO)
+
+---
+
+*Last Updated: 2025-10-15*

apps/web/drizzle/0011_add_room_game_configs.sql

@@ -0,0 +1,33 @@
+-- Create room_game_configs table for normalized game settings storage
+-- This migration is safe to run multiple times (uses IF NOT EXISTS)
+
+-- Create the table
+CREATE TABLE IF NOT EXISTS `room_game_configs` (
+	`id` text PRIMARY KEY NOT NULL,
+	`room_id` text NOT NULL,
+	`game_name` text NOT NULL,
+	`config` text NOT NULL,
+	`created_at` integer NOT NULL,
+	`updated_at` integer NOT NULL,
+	FOREIGN KEY (`room_id`) REFERENCES `arcade_rooms`(`id`) ON UPDATE no action ON DELETE cascade
+);
+--> statement-breakpoint
+
+-- Create unique index
+CREATE UNIQUE INDEX IF NOT EXISTS `room_game_idx` ON `room_game_configs` (`room_id`,`game_name`);
+--> statement-breakpoint
+
+-- Migrate existing game configs from arcade_rooms.game_config column
+-- This INSERT will only run if data hasn't been migrated yet
+INSERT OR IGNORE INTO room_game_configs (id, room_id, game_name, config, created_at, updated_at)
+SELECT
+  lower(hex(randomblob(16))) as id,
+  id as room_id,
+  game_name,
+  game_config as config,
+  created_at,
+  last_activity as updated_at
+FROM arcade_rooms
+WHERE game_config IS NOT NULL
+  AND game_name IS NOT NULL
+  AND game_name IN ('matching', 'memory-quiz', 'complement-race');

apps/web/drizzle/meta/_journal.json

@@ -78,6 +78,13 @@
       "when": 1760700000000,
       "tag": "0010_make_game_name_nullable",
       "breakpoints": true
+    },
+    {
+      "idx": 11,
+      "version": "7",
+      "when": 1760800000000,
+      "tag": "0011_add_room_game_configs",
+      "breakpoints": true
     }
   ]
 }

apps/web/package.json

@@ -59,6 +59,7 @@
     "drizzle-orm": "^0.44.6",
     "emojibase-data": "^16.0.3",
     "jose": "^6.1.0",
+    "js-yaml": "^4.1.0",
     "lucide-react": "^0.294.0",
     "make-plural": "^7.4.0",
     "nanoid": "^5.1.6",
@@ -69,7 +70,8 @@
     "react-dom": "^18.2.0",
     "react-resizable-layout": "^0.7.3",
     "socket.io": "^4.8.1",
-    "socket.io-client": "^4.8.1"
+    "socket.io-client": "^4.8.1",
+    "zod": "^4.1.12"
   },
   "devDependencies": {
     "@playwright/test": "^1.55.1",
@@ -80,6 +82,7 @@
     "@testing-library/react": "^16.3.0",
     "@types/bcryptjs": "^2.4.6",
     "@types/better-sqlite3": "^7.6.13",
+    "@types/js-yaml": "^4.0.9",
     "@types/node": "^20.0.0",
     "@types/react": "^18.2.0",
     "@types/react-dom": "^18.2.0",

apps/web/src/app/api/arcade/rooms/[roomId]/settings/route.ts

@@ -7,6 +7,9 @@ import { recordRoomMemberHistory } from '@/lib/arcade/room-member-history'
 import { getRoomMembers } from '@/lib/arcade/room-membership'
 import { getSocketIO } from '@/lib/socket-io'
 import { getViewerId } from '@/lib/viewer'
+import { getAllGameConfigs, setGameConfig } from '@/lib/arcade/game-config-helpers'
+import { isValidGameName } from '@/lib/arcade/validators'
+import type { GameName } from '@/lib/arcade/validators'
 
 type RouteContext = {
   params: Promise<{ roomId: string }>
@@ -18,8 +21,11 @@ type RouteContext = {
  * Body:
  *   - accessMode?: 'open' | 'locked' | 'retired' | 'password' | 'restricted' | 'approval-only'
  *   - password?: string (plain text, will be hashed)
- *   - gameName?: 'matching' | 'memory-quiz' | 'complement-race' | null (select game for room)
+ *   - gameName?: string | null (any game with a registered validator)
  *   - gameConfig?: object (game-specific settings)
+ *
+ * Note: gameName is validated at runtime against the validator registry.
+ * No need to update this file when adding new games!
  */
 export async function PATCH(req: NextRequest, context: RouteContext) {
   try {
@@ -27,6 +33,36 @@ export async function PATCH(req: NextRequest, context: RouteContext) {
     const viewerId = await getViewerId()
     const body = await req.json()
 
+    console.log(
+      '[Settings API] PATCH request received:',
+      JSON.stringify(
+        {
+          roomId,
+          body,
+        },
+        null,
+        2
+      )
+    )
+
+    // Read current room state from database BEFORE any changes
+    const [currentRoom] = await db
+      .select()
+      .from(schema.arcadeRooms)
+      .where(eq(schema.arcadeRooms.id, roomId))
+
+    console.log(
+      '[Settings API] Current room state in database BEFORE update:',
+      JSON.stringify(
+        {
+          gameName: currentRoom?.gameName,
+          gameConfig: currentRoom?.gameConfig,
+        },
+        null,
+        2
+      )
+    )
+
     // Check if user is the host
     const members = await getRoomMembers(roomId)
     const currentMember = members.find((m) => m.userId === viewerId)
@@ -60,11 +96,15 @@ export async function PATCH(req: NextRequest, context: RouteContext) {
       )
     }
 
-    // Validate gameName if provided
+    // Validate gameName if provided - check against validator registry at runtime
     if (body.gameName !== undefined && body.gameName !== null) {
-      const validGames = ['matching', 'memory-quiz', 'complement-race']
-      if (!validGames.includes(body.gameName)) {
-        return NextResponse.json({ error: 'Invalid game name' }, { status: 400 })
+      if (!isValidGameName(body.gameName)) {
+        return NextResponse.json(
+          {
+            error: `Invalid game name: ${body.gameName}. Game must have a registered validator.`,
+          },
+          { status: 400 }
+        )
       }
     }
 
@@ -92,11 +132,23 @@ export async function PATCH(req: NextRequest, context: RouteContext) {
       updateData.gameName = body.gameName
     }
 
-    // Update game config if provided
-    if (body.gameConfig !== undefined) {
-      updateData.gameConfig = body.gameConfig
+    // Handle game config updates - write to new room_game_configs table
+    if (body.gameConfig !== undefined && body.gameConfig !== null) {
+      // body.gameConfig is expected to be nested by game name: { matching: {...}, memory-quiz: {...} }
+      // Extract each game's config and write to the new table
+      for (const [gameName, config] of Object.entries(body.gameConfig)) {
+        if (config && typeof config === 'object') {
+          await setGameConfig(roomId, gameName as GameName, config)
+          console.log(`[Settings API] Wrote ${gameName} config to room_game_configs table`)
+        }
+      }
     }
 
+    console.log(
+      '[Settings API] Update data to be written to database:',
+      JSON.stringify(updateData, null, 2)
+    )
+
     // If game is being changed (or cleared), delete the existing arcade session
     // This ensures a fresh session will be created with the new game settings
     if (body.gameName !== undefined) {
@@ -104,12 +156,30 @@ export async function PATCH(req: NextRequest, context: RouteContext) {
       await db.delete(schema.arcadeSessions).where(eq(schema.arcadeSessions.roomId, roomId))
     }
 
-    // Update room settings
-    const [updatedRoom] = await db
-      .update(schema.arcadeRooms)
-      .set(updateData)
-      .where(eq(schema.arcadeRooms.id, roomId))
-      .returning()
+    // Update room settings (only if there's something to update)
+    let updatedRoom = currentRoom
+    if (Object.keys(updateData).length > 0) {
+      ;[updatedRoom] = await db
+        .update(schema.arcadeRooms)
+        .set(updateData)
+        .where(eq(schema.arcadeRooms.id, roomId))
+        .returning()
+    }
+
+    // Get aggregated game configs from new table
+    const gameConfig = await getAllGameConfigs(roomId)
+
+    console.log(
+      '[Settings API] Room state in database AFTER update:',
+      JSON.stringify(
+        {
+          gameName: updatedRoom.gameName,
+          gameConfig,
+        },
+        null,
+        2
+      )
+    )
 
     // Broadcast game change to all room members
     if (body.gameName !== undefined) {
@@ -117,11 +187,17 @@ export async function PATCH(req: NextRequest, context: RouteContext) {
       if (io) {
         try {
           console.log(`[Settings API] Broadcasting game change to room ${roomId}: ${body.gameName}`)
-          io.to(`room:${roomId}`).emit('room-game-changed', {
+          const broadcastData: {
+            roomId: string
+            gameName: string | null
+            gameConfig?: Record<string, unknown>
+          } = {
             roomId,
             gameName: body.gameName,
-            gameConfig: body.gameConfig || {},
-          })
+            gameConfig, // Include aggregated configs from new table
+          }
+
+          io.to(`room:${roomId}`).emit('room-game-changed', broadcastData)
         } catch (socketError) {
           console.error('[Settings API] Failed to broadcast game change:', socketError)
         }
@@ -194,7 +270,15 @@ export async function PATCH(req: NextRequest, context: RouteContext) {
       }
     }
 
-    return NextResponse.json({ room: updatedRoom }, { status: 200 })
+    return NextResponse.json(
+      {
+        room: {
+          ...updatedRoom,
+          gameConfig, // Include aggregated configs from new table
+        },
+      },
+      { status: 200 }
+    )
   } catch (error: any) {
     console.error('Failed to update room settings:', error)
     return NextResponse.json({ error: 'Failed to update room settings' }, { status: 500 })

apps/web/src/app/api/arcade/rooms/current/route.ts

@@ -4,6 +4,7 @@ import { getRoomById } from '@/lib/arcade/room-manager'
 import { getRoomMembers } from '@/lib/arcade/room-membership'
 import { getRoomActivePlayers } from '@/lib/arcade/player-manager'
 import { getViewerId } from '@/lib/viewer'
+import { getAllGameConfigs } from '@/lib/arcade/game-config-helpers'
 
 /**
  * GET /api/arcade/rooms/current
@@ -28,6 +29,22 @@ export async function GET() {
       return NextResponse.json({ error: 'Room not found' }, { status: 404 })
     }
 
+    // Get game configs from new room_game_configs table
+    const gameConfig = await getAllGameConfigs(roomId)
+
+    console.log(
+      '[Current Room API] Room data READ from database:',
+      JSON.stringify(
+        {
+          roomId,
+          gameName: room.gameName,
+          gameConfig,
+        },
+        null,
+        2
+      )
+    )
+
     // Get members
     const members = await getRoomMembers(roomId)
 
@@ -41,7 +58,10 @@ export async function GET() {
     }
 
     return NextResponse.json({
-      room,
+      room: {
+        ...room,
+        gameConfig, // Override with configs from new table
+      },
       members,
       memberPlayers: memberPlayersObj,
     })

apps/web/src/app/api/arcade/rooms/route.ts

@@ -3,7 +3,7 @@ import { createRoom, listActiveRooms } from '@/lib/arcade/room-manager'
 import { addRoomMember, getRoomMembers, isMember } from '@/lib/arcade/room-membership'
 import { getRoomActivePlayers } from '@/lib/arcade/player-manager'
 import { getViewerId } from '@/lib/viewer'
-import type { GameName } from '@/lib/arcade/validation'
+import { hasValidator, type GameName } from '@/lib/arcade/validators'
 
 /**
  * GET /api/arcade/rooms
@@ -72,8 +72,7 @@ export async function POST(req: NextRequest) {
 
     // Validate game name if provided (gameName is now optional)
     if (body.gameName) {
-      const validGames: GameName[] = ['matching', 'memory-quiz', 'complement-race']
-      if (!validGames.includes(body.gameName)) {
+      if (!hasValidator(body.gameName)) {
         return NextResponse.json({ error: 'Invalid game name' }, { status: 400 })
       }
     }

apps/web/src/app/arcade/matching/context/RoomMemoryPairsProvider.tsx

@@ -2,7 +2,7 @@
 
 import { type ReactNode, useCallback, useEffect, useMemo } from 'react'
 import { useArcadeSession } from '@/hooks/useArcadeSession'
-import { useRoomData } from '@/hooks/useRoomData'
+import { useRoomData, useUpdateGameConfig } from '@/hooks/useRoomData'
 import { useViewerId } from '@/hooks/useViewerId'
 import {
   buildPlayerMetadata as buildPlayerMetadataUtil,
@@ -240,6 +240,7 @@ export function RoomMemoryPairsProvider({ children }: { children: ReactNode }) {
   const { data: viewerId } = useViewerId()
   const { roomData } = useRoomData() // Fetch room data for room-based play
   const { activePlayerCount, activePlayers: activePlayerIds, players } = useGameMode()
+  const { mutate: updateGameConfig } = useUpdateGameConfig()
 
   // Get active player IDs directly as strings (UUIDs)
   const activePlayers = Array.from(activePlayerIds)
@@ -247,8 +248,77 @@ export function RoomMemoryPairsProvider({ children }: { children: ReactNode }) {
   // Derive game mode from active player count
   const gameMode = activePlayerCount > 1 ? 'multiplayer' : 'single'
 
-  // NO LOCAL STATE - Configuration lives in session state
-  // Changes are sent as moves and synchronized across all room members
+  // Track roomData.gameConfig changes
+  useEffect(() => {
+    console.log(
+      '[RoomMemoryPairsProvider] roomData.gameConfig changed:',
+      JSON.stringify(
+        {
+          gameConfig: roomData?.gameConfig,
+          roomId: roomData?.id,
+          gameName: roomData?.gameName,
+        },
+        null,
+        2
+      )
+    )
+  }, [roomData?.gameConfig, roomData?.id, roomData?.gameName])
+
+  // Merge saved game config from room with initialState
+  // Settings are scoped by game name to preserve settings when switching games
+  const mergedInitialState = useMemo(() => {
+    const gameConfig = roomData?.gameConfig as Record<string, any> | null | undefined
+    console.log(
+      '[RoomMemoryPairsProvider] Loading settings from database:',
+      JSON.stringify(
+        {
+          gameConfig,
+          roomId: roomData?.id,
+        },
+        null,
+        2
+      )
+    )
+
+    if (!gameConfig) {
+      console.log('[RoomMemoryPairsProvider] No gameConfig, using initialState')
+      return initialState
+    }
+
+    // Get settings for this specific game (matching)
+    const savedConfig = gameConfig.matching as Record<string, any> | null | undefined
+    console.log(
+      '[RoomMemoryPairsProvider] Saved config for matching:',
+      JSON.stringify(savedConfig, null, 2)
+    )
+
+    if (!savedConfig) {
+      console.log('[RoomMemoryPairsProvider] No saved config for matching, using initialState')
+      return initialState
+    }
+
+    const merged = {
+      ...initialState,
+      // Restore settings from saved config
+      gameType: savedConfig.gameType ?? initialState.gameType,
+      difficulty: savedConfig.difficulty ?? initialState.difficulty,
+      turnTimer: savedConfig.turnTimer ?? initialState.turnTimer,
+    }
+    console.log(
+      '[RoomMemoryPairsProvider] Merged state:',
+      JSON.stringify(
+        {
+          gameType: merged.gameType,
+          difficulty: merged.difficulty,
+          turnTimer: merged.turnTimer,
+        },
+        null,
+        2
+      )
+    )
+
+    return merged
+  }, [roomData?.gameConfig])
 
   // Arcade session integration WITH room sync
   const {
@@ -259,7 +329,7 @@ export function RoomMemoryPairsProvider({ children }: { children: ReactNode }) {
   } = useArcadeSession<MemoryPairsState>({
     userId: viewerId || '',
     roomId: roomData?.id, // CRITICAL: Pass roomId for network sync across room members
-    initialState,
+    initialState: mergedInitialState,
     applyMove: applyMoveOptimistically,
   })
 
@@ -498,6 +568,8 @@ export function RoomMemoryPairsProvider({ children }: { children: ReactNode }) {
 
   const setGameType = useCallback(
     (gameType: typeof state.gameType) => {
+      console.log('[RoomMemoryPairsProvider] setGameType called:', gameType)
+
       // Use first active player as playerId, or empty string if none
       const playerId = activePlayers[0] || ''
       sendMove({
@@ -506,12 +578,45 @@ export function RoomMemoryPairsProvider({ children }: { children: ReactNode }) {
         userId: viewerId || '',
         data: { field: 'gameType', value: gameType },
       })
+
+      // Save setting to room's gameConfig for persistence
+      if (roomData?.id) {
+        const currentGameConfig = (roomData.gameConfig as Record<string, any>) || {}
+        const currentMatchingConfig = (currentGameConfig.matching as Record<string, any>) || {}
+
+        const updatedConfig = {
+          ...currentGameConfig,
+          matching: {
+            ...currentMatchingConfig,
+            gameType,
+          },
+        }
+        console.log(
+          '[RoomMemoryPairsProvider] Saving gameType to database:',
+          JSON.stringify(
+            {
+              roomId: roomData.id,
+              updatedConfig,
+            },
+            null,
+            2
+          )
+        )
+        updateGameConfig({
+          roomId: roomData.id,
+          gameConfig: updatedConfig,
+        })
+      } else {
+        console.warn('[RoomMemoryPairsProvider] Cannot save gameType - no roomData.id')
+      }
     },
-    [activePlayers, sendMove, viewerId]
+    [activePlayers, sendMove, viewerId, roomData?.id, roomData?.gameConfig, updateGameConfig]
   )
 
   const setDifficulty = useCallback(
     (difficulty: typeof state.difficulty) => {
+      console.log('[RoomMemoryPairsProvider] setDifficulty called:', difficulty)
+
       const playerId = activePlayers[0] || ''
       sendMove({
         type: 'SET_CONFIG',
@@ -519,12 +624,45 @@ export function RoomMemoryPairsProvider({ children }: { children: ReactNode }) {
         userId: viewerId || '',
         data: { field: 'difficulty', value: difficulty },
       })
+
+      // Save setting to room's gameConfig for persistence
+      if (roomData?.id) {
+        const currentGameConfig = (roomData.gameConfig as Record<string, any>) || {}
+        const currentMatchingConfig = (currentGameConfig.matching as Record<string, any>) || {}
+
+        const updatedConfig = {
+          ...currentGameConfig,
+          matching: {
+            ...currentMatchingConfig,
+            difficulty,
+          },
+        }
+        console.log(
+          '[RoomMemoryPairsProvider] Saving difficulty to database:',
+          JSON.stringify(
+            {
+              roomId: roomData.id,
+              updatedConfig,
+            },
+            null,
+            2
+          )
+        )
+        updateGameConfig({
+          roomId: roomData.id,
+          gameConfig: updatedConfig,
+        })
+      } else {
+        console.warn('[RoomMemoryPairsProvider] Cannot save difficulty - no roomData.id')
+      }
     },
-    [activePlayers, sendMove, viewerId]
+    [activePlayers, sendMove, viewerId, roomData?.id, roomData?.gameConfig, updateGameConfig]
   )
 
   const setTurnTimer = useCallback(
     (turnTimer: typeof state.turnTimer) => {
+      console.log('[RoomMemoryPairsProvider] setTurnTimer called:', turnTimer)
+
       const playerId = activePlayers[0] || ''
       sendMove({
         type: 'SET_CONFIG',
@@ -532,8 +670,39 @@ export function RoomMemoryPairsProvider({ children }: { children: ReactNode }) {
         userId: viewerId || '',
         data: { field: 'turnTimer', value: turnTimer },
       })
+
+      // Save setting to room's gameConfig for persistence
+      if (roomData?.id) {
+        const currentGameConfig = (roomData.gameConfig as Record<string, any>) || {}
+        const currentMatchingConfig = (currentGameConfig.matching as Record<string, any>) || {}
+
+        const updatedConfig = {
+          ...currentGameConfig,
+          matching: {
+            ...currentMatchingConfig,
+            turnTimer,
+          },
+        }
+        console.log(
+          '[RoomMemoryPairsProvider] Saving turnTimer to database:',
+          JSON.stringify(
+            {
+              roomId: roomData.id,
+              updatedConfig,
+            },
+            null,
+            2
+          )
+        )
+        updateGameConfig({
+          roomId: roomData.id,
+          gameConfig: updatedConfig,
+        })
+      } else {
+        console.warn('[RoomMemoryPairsProvider] Cannot save turnTimer - no roomData.id')
+      }
     },
-    [activePlayers, sendMove, viewerId]
+    [activePlayers, sendMove, viewerId, roomData?.id, roomData?.gameConfig, updateGameConfig]
   )
 
   const goToSetup = useCallback(() => {

apps/web/src/app/arcade/memory-quiz/context/RoomMemoryQuizProvider.tsx

@@ -210,23 +210,19 @@ export function RoomMemoryQuizProvider({ children }: { children: ReactNode }) {
   // Settings are scoped by game name to preserve settings when switching games
   const mergedInitialState = useMemo(() => {
     const gameConfig = roomData?.gameConfig as Record<string, any> | null | undefined
-    console.log('[RoomMemoryQuizProvider] Initializing - gameConfig:', gameConfig)
 
     if (!gameConfig) {
-      console.log('[RoomMemoryQuizProvider] No gameConfig, using initialState')
       return initialState
     }
 
     // Get settings for this specific game (memory-quiz)
     const savedConfig = gameConfig['memory-quiz'] as Record<string, any> | null | undefined
-    console.log('[RoomMemoryQuizProvider] Loading saved config for memory-quiz:', savedConfig)
 
     if (!savedConfig) {
-      console.log('[RoomMemoryQuizProvider] No saved config for memory-quiz, using initialState')
       return initialState
     }
 
-    const merged = {
+    return {
       ...initialState,
       // Restore settings from saved config
       selectedCount: savedConfig.selectedCount ?? initialState.selectedCount,
@@ -234,14 +230,6 @@ export function RoomMemoryQuizProvider({ children }: { children: ReactNode }) {
       selectedDifficulty: savedConfig.selectedDifficulty ?? initialState.selectedDifficulty,
       playMode: savedConfig.playMode ?? initialState.playMode,
     }
-    console.log('[RoomMemoryQuizProvider] Merged state:', {
-      selectedCount: merged.selectedCount,
-      displayTime: merged.displayTime,
-      selectedDifficulty: merged.selectedDifficulty,
-      playMode: merged.playMode,
-    })
-
-    return merged
   }, [roomData?.gameConfig])
 
   // Arcade session integration WITH room sync
@@ -399,26 +387,19 @@ export function RoomMemoryQuizProvider({ children }: { children: ReactNode }) {
       // Settings are scoped by game name to preserve settings when switching games
       if (roomData?.id) {
         const currentGameConfig = (roomData.gameConfig as Record<string, any>) || {}
-        console.log('[RoomMemoryQuizProvider] Current gameConfig:', currentGameConfig)
-
         const currentMemoryQuizConfig =
           (currentGameConfig['memory-quiz'] as Record<string, any>) || {}
-        console.log('[RoomMemoryQuizProvider] Current memory-quiz config:', currentMemoryQuizConfig)
 
-        const updatedConfig = {
-          ...currentGameConfig,
-          'memory-quiz': {
-            ...currentMemoryQuizConfig,
-            [field]: value,
-          },
-        }
-        console.log('[RoomMemoryQuizProvider] Saving updated gameConfig:', updatedConfig)
         updateGameConfig({
           roomId: roomData.id,
-          gameConfig: updatedConfig,
+          gameConfig: {
+            ...currentGameConfig,
+            'memory-quiz': {
+              ...currentMemoryQuizConfig,
+              [field]: value,
+            },
+          },
         })
-      } else {
-        console.warn('[RoomMemoryQuizProvider] No roomData.id, cannot save config')
       }
     },
     [viewerId, sendMove, roomData?.id, roomData?.gameConfig, updateGameConfig]

apps/web/src/app/arcade/room/page.tsx

@@ -10,6 +10,7 @@ import { GAMES_CONFIG } from '@/components/GameSelector'
 import type { GameType } from '@/components/GameSelector'
 import { PageWithNav } from '@/components/PageWithNav'
 import { css } from '../../../../styled-system/css'
+import { getAllGames, getGame, hasGame } from '@/lib/arcade/game-registry'
 
 // Map GameType keys to internal game names
 const GAME_TYPE_TO_NAME: Record<GameType, string> = {
@@ -89,13 +90,35 @@ export default function RoomPage() {
     const handleGameSelect = (gameType: GameType) => {
       console.log('[RoomPage] handleGameSelect called with gameType:', gameType)
 
-      const gameConfig = GAMES_CONFIG[gameType]
+      // Check if it's a registry game first
+      if (hasGame(gameType)) {
+        const gameDef = getGame(gameType)
+        if (!gameDef?.manifest.available) {
+          console.log('[RoomPage] Registry game not available, blocking selection')
+          return
+        }
+
+        console.log('[RoomPage] Selecting registry game:', gameType)
+        setRoomGame({
+          roomId: roomData.id,
+          gameName: gameType, // Use the game name directly for registry games
+        })
+        return
+      }
+
+      // Legacy game handling
+      const gameConfig = GAMES_CONFIG[gameType as keyof typeof GAMES_CONFIG]
+      if (!gameConfig) {
+        console.log('[RoomPage] Unknown game type:', gameType)
+        return
+      }
+
       console.log('[RoomPage] Game config:', {
         name: gameConfig.name,
-        available: gameConfig.available,
+        available: 'available' in gameConfig ? gameConfig.available : true,
       })
 
-      if (gameConfig.available === false) {
+      if ('available' in gameConfig && gameConfig.available === false) {
         console.log('[RoomPage] Game not available, blocking selection')
         return // Don't allow selecting unavailable games
       }
@@ -160,64 +183,158 @@ export default function RoomPage() {
               width: '100%',
             })}
           >
-            {Object.entries(GAMES_CONFIG).map(([gameType, config]) => (
-              <button
-                key={gameType}
-                onClick={() => handleGameSelect(gameType as GameType)}
-                disabled={config.available === false}
-                className={css({
-                  background: config.gradient,
-                  border: '2px solid',
-                  borderColor: config.borderColor || 'blue.200',
-                  borderRadius: '2xl',
-                  padding: '6',
-                  cursor: config.available === false ? 'not-allowed' : 'pointer',
-                  opacity: config.available === false ? 0.5 : 1,
-                  transition: 'all 0.3s ease',
-                  _hover:
-                    config.available === false
+            {/* Legacy games */}
+            {Object.entries(GAMES_CONFIG).map(([gameType, config]) => {
+              const isAvailable = !('available' in config) || config.available !== false
+              return (
+                <button
+                  key={gameType}
+                  onClick={() => handleGameSelect(gameType as GameType)}
+                  disabled={!isAvailable}
+                  className={css({
+                    background: config.gradient,
+                    border: '2px solid',
+                    borderColor: config.borderColor || 'blue.200',
+                    borderRadius: '2xl',
+                    padding: '6',
+                    cursor: !isAvailable ? 'not-allowed' : 'pointer',
+                    opacity: !isAvailable ? 0.5 : 1,
+                    transition: 'all 0.3s ease',
+                    _hover: !isAvailable
                       ? {}
                       : {
                           transform: 'translateY(-4px) scale(1.02)',
                           boxShadow: '0 20px 40px rgba(59, 130, 246, 0.2)',
                         },
-                })}
-              >
-                <div
-                  className={css({
-                    fontSize: '4xl',
-                    mb: '2',
                   })}
                 >
-                  {config.icon}
-                </div>
-                <h3
+                  <div
+                    className={css({
+                      fontSize: '4xl',
+                      mb: '2',
+                    })}
+                  >
+                    {config.icon}
+                  </div>
+                  <h3
+                    className={css({
+                      fontSize: 'xl',
+                      fontWeight: 'bold',
+                      color: 'gray.900',
+                      mb: '2',
+                    })}
+                  >
+                    {config.name}
+                  </h3>
+                  <p
+                    className={css({
+                      fontSize: 'sm',
+                      color: 'gray.600',
+                    })}
+                  >
+                    {config.description}
+                  </p>
+                </button>
+              )
+            })}
+
+            {/* Registry games */}
+            {getAllGames().map((gameDef) => {
+              const isAvailable = gameDef.manifest.available
+              return (
+                <button
+                  key={gameDef.manifest.name}
+                  onClick={() => handleGameSelect(gameDef.manifest.name)}
+                  disabled={!isAvailable}
                   className={css({
-                    fontSize: 'xl',
-                    fontWeight: 'bold',
-                    color: 'gray.900',
-                    mb: '2',
+                    background: gameDef.manifest.gradient,
+                    border: '2px solid',
+                    borderColor: gameDef.manifest.borderColor,
+                    borderRadius: '2xl',
+                    padding: '6',
+                    cursor: !isAvailable ? 'not-allowed' : 'pointer',
+                    opacity: !isAvailable ? 0.5 : 1,
+                    transition: 'all 0.3s ease',
+                    _hover: !isAvailable
+                      ? {}
+                      : {
+                          transform: 'translateY(-4px) scale(1.02)',
+                          boxShadow: '0 20px 40px rgba(59, 130, 246, 0.2)',
+                        },
                   })}
                 >
-                  {config.name}
-                </h3>
-                <p
-                  className={css({
-                    fontSize: 'sm',
-                    color: 'gray.600',
-                  })}
-                >
-                  {config.description}
-                </p>
-              </button>
-            ))}
+                  <div
+                    className={css({
+                      fontSize: '4xl',
+                      mb: '2',
+                    })}
+                  >
+                    {gameDef.manifest.icon}
+                  </div>
+                  <h3
+                    className={css({
+                      fontSize: 'xl',
+                      fontWeight: 'bold',
+                      color: 'gray.900',
+                      mb: '2',
+                    })}
+                  >
+                    {gameDef.manifest.displayName}
+                  </h3>
+                  <p
+                    className={css({
+                      fontSize: 'sm',
+                      color: 'gray.600',
+                    })}
+                  >
+                    {gameDef.manifest.description}
+                  </p>
+                </button>
+              )
+            })}
           </div>
         </div>
       </PageWithNav>
     )
   }
 
-  // Render the appropriate game based on room's gameName
+  // Check if this is a registry game first
+  if (hasGame(roomData.gameName)) {
+    const gameDef = getGame(roomData.gameName)
+    if (!gameDef) {
+      return (
+        <PageWithNav
+          navTitle="Game Not Found"
+          navEmoji="⚠️"
+          emphasizePlayerSelection={true}
+          onExitSession={() => router.push('/arcade')}
+        >
+          <div
+            style={{
+              display: 'flex',
+              alignItems: 'center',
+              justifyContent: 'center',
+              height: '100vh',
+              fontSize: '18px',
+              color: '#666',
+            }}
+          >
+            Game "{roomData.gameName}" not found in registry
+          </div>
+        </PageWithNav>
+      )
+    }
+
+    // Render registry game dynamically
+    const { Provider, GameComponent } = gameDef
+    return (
+      <Provider>
+        <GameComponent />
+      </Provider>
+    )
+  }
+
+  // Render legacy games based on room's gameName
   switch (roomData.gameName) {
     case 'matching':
       return (

apps/web/src/arcade-games/README.md

@@ -0,0 +1,816 @@
+# Arcade Game System
+
+A modular, plugin-based architecture for building multiplayer arcade games with real-time synchronization.
+
+## Table of Contents
+
+- [Overview](#overview)
+- [Architecture](#architecture)
+- [Game SDK](#game-sdk)
+- [Creating a New Game](#creating-a-new-game)
+- [File Structure](#file-structure)
+- [Examples](#examples)
+- [Best Practices](#best-practices)
+- [Troubleshooting](#troubleshooting)
+
+---
+
+## Overview
+
+### Goals
+
+1. **Modularity**: Each game is self-contained and independently deployable
+2. **Type Safety**: Full TypeScript support with compile-time validation
+3. **Real-time Sync**: Built-in multiplayer support via WebSocket
+4. **Optimistic Updates**: Instant client feedback with server validation
+5. **Consistent UX**: Shared navigation, player management, and room features
+
+### Key Features
+
+- **Plugin Architecture**: Games register themselves with a central registry
+- **Stable SDK API**: Games only import from `@/lib/arcade/game-sdk`
+- **Server-side Validation**: All moves validated server-side with client rollback
+- **Automatic State Sync**: Multi-client synchronization handled automatically
+- **Turn Indicators**: Built-in UI for showing active player
+- **Error Handling**: Standardized error feedback to users
+
+---
+
+## Architecture
+
+### System Components
+
+```
+┌─────────────────────────────────────────────────────────────┐
+│                     Game Registry                            │
+│  - Registers all available games                            │
+│  - Provides game discovery                                  │
+└─────────────────────────────────────────────────────────────┘
+                            │
+                            ▼
+┌─────────────────────────────────────────────────────────────┐
+│                      Game SDK                                │
+│  - Stable API surface for games                             │
+│  - React hooks (useArcadeSession, useRoomData, etc.)        │
+│  - Type definitions and utilities                           │
+└─────────────────────────────────────────────────────────────┘
+                            │
+                            ▼
+┌─────────────────────────────────────────────────────────────┐
+│                   Individual Games                           │
+│  number-guesser/                                            │
+│    ├── index.ts          (Game definition)                  │
+│    ├── Validator.ts      (Server validation)                │
+│    ├── Provider.tsx      (Client state management)          │
+│    ├── GameComponent.tsx (Main UI)                          │
+│    ├── types.ts          (TypeScript types)                 │
+│    └── components/       (Phase UIs)                        │
+└─────────────────────────────────────────────────────────────┘
+```
+
+### Data Flow
+
+```
+User Action → Provider (sendMove)
+              ↓
+        useArcadeSession
+              ↓
+        Optimistic Update (instant UI feedback)
+              ↓
+        WebSocket → Server
+              ↓
+        Validator.validateMove()
+              ↓
+        ✓ Valid: State Update → Broadcast
+        ✗ Invalid: Reject → Client Rollback
+              ↓
+        Client receives validated state
+```
+
+---
+
+## Game SDK
+
+### Core API Surface
+
+```typescript
+import {
+  // Types
+  type GameDefinition,
+  type GameValidator,
+  type GameState,
+  type GameMove,
+  type GameConfig,
+  type ValidationResult,
+
+  // React Hooks
+  useArcadeSession,
+  useRoomData,
+  useGameMode,
+  useViewerId,
+  useUpdateGameConfig,
+
+  // Utilities
+  defineGame,
+  buildPlayerMetadata,
+
+} from '@/lib/arcade/game-sdk'
+```
+
+### Key Concepts
+
+#### GameDefinition
+
+Complete description of a game:
+
+```typescript
+interface GameDefinition<TConfig, TState, TMove> {
+  manifest: GameManifest          // Display info, max players, etc.
+  Provider: GameProviderComponent // React context provider
+  GameComponent: GameComponent    // Main UI component
+  validator: GameValidator        // Server-side validation
+  defaultConfig: TConfig          // Default game settings
+}
+```
+
+#### GameState
+
+The complete game state that's synchronized across all clients:
+
+```typescript
+interface GameState {
+  gamePhase: string                          // Current phase (setup, playing, results)
+  activePlayers: string[]                    // Array of player IDs
+  playerMetadata: Record<string, PlayerMeta> // Player info (name, emoji, etc.)
+  // ... game-specific state
+}
+```
+
+#### GameMove
+
+Actions that players take, validated server-side:
+
+```typescript
+interface GameMove {
+  type: string           // Move type (e.g., 'FLIP_CARD', 'MAKE_GUESS')
+  playerId: string       // Player making the move
+  userId: string         // User ID (for authentication)
+  timestamp: number      // Client timestamp
+  data: Record<string, unknown> // Move-specific payload
+}
+```
+
+#### GameValidator
+
+Server-side validation logic:
+
+```typescript
+interface GameValidator<TState, TMove> {
+  validateMove(state: TState, move: TMove): ValidationResult
+  isGameComplete(state: TState): boolean
+  getInitialState(config: unknown): TState
+}
+```
+
+---
+
+## Creating a New Game
+
+### Step 1: Create Game Directory
+
+```bash
+mkdir -p src/arcade-games/my-game/components
+```
+
+### Step 2: Define Types (`types.ts`)
+
+```typescript
+import type { GameConfig, GameMove, GameState } from '@/lib/arcade/game-sdk'
+
+// Game configuration (persisted to database)
+export interface MyGameConfig extends GameConfig {
+  difficulty: number
+  timer: number
+}
+
+// Game state (synchronized across clients)
+export interface MyGameState extends GameState {
+  gamePhase: 'setup' | 'playing' | 'results'
+  activePlayers: string[]
+  playerMetadata: Record<string, PlayerMetadata>
+  currentPlayer: string
+  score: Record<string, number>
+  // ... your game-specific state
+}
+
+// Move types
+export type MyGameMove =
+  | { type: 'START_GAME'; playerId: string; userId: string; timestamp: number; data: { activePlayers: string[] } }
+  | { type: 'MAKE_MOVE'; playerId: string; userId: string; timestamp: number; data: { /* move data */ } }
+  | { type: 'END_GAME'; playerId: string; userId: string; timestamp: number; data: {} }
+```
+
+### Step 3: Create Validator (`Validator.ts`)
+
+```typescript
+import type { GameValidator, ValidationResult } from '@/lib/arcade/game-sdk'
+import type { MyGameState, MyGameMove } from './types'
+
+export class MyGameValidator implements GameValidator<MyGameState, MyGameMove> {
+  validateMove(state: MyGameState, move: MyGameMove): ValidationResult {
+    switch (move.type) {
+      case 'START_GAME':
+        return this.validateStartGame(state, move.data.activePlayers)
+      case 'MAKE_MOVE':
+        return this.validateMakeMove(state, move.playerId, move.data)
+      default:
+        return { valid: false, error: 'Unknown move type' }
+    }
+  }
+
+  private validateStartGame(state: MyGameState, activePlayers: string[]): ValidationResult {
+    if (activePlayers.length < 2) {
+      return { valid: false, error: 'Need at least 2 players' }
+    }
+
+    const newState: MyGameState = {
+      ...state,
+      gamePhase: 'playing',
+      activePlayers,
+      currentPlayer: activePlayers[0],
+      score: activePlayers.reduce((acc, p) => ({ ...acc, [p]: 0 }), {}),
+    }
+
+    return { valid: true, newState }
+  }
+
+  // ... more validation methods
+
+  isGameComplete(state: MyGameState): boolean {
+    return state.gamePhase === 'results'
+  }
+
+  getInitialState(config: unknown): MyGameState {
+    const { difficulty, timer } = config as MyGameConfig
+    return {
+      difficulty,
+      timer,
+      gamePhase: 'setup',
+      activePlayers: [],
+      playerMetadata: {},
+      currentPlayer: '',
+      score: {},
+    }
+  }
+}
+
+export const myGameValidator = new MyGameValidator()
+```
+
+### Step 4: Create Provider (`Provider.tsx`)
+
+```typescript
+'use client'
+
+import { createContext, useCallback, useContext, useMemo } from 'react'
+import {
+  type GameMove,
+  buildPlayerMetadata,
+  useArcadeSession,
+  useGameMode,
+  useRoomData,
+  useViewerId,
+} from '@/lib/arcade/game-sdk'
+import type { MyGameState } from './types'
+
+interface MyGameContextValue {
+  state: MyGameState
+  lastError: string | null
+  startGame: () => void
+  makeMove: (data: any) => void
+  clearError: () => void
+  exitSession: () => void
+}
+
+const MyGameContext = createContext<MyGameContextValue | null>(null)
+
+export function useMyGame() {
+  const context = useContext(MyGameContext)
+  if (!context) throw new Error('useMyGame must be used within MyGameProvider')
+  return context
+}
+
+export function MyGameProvider({ children }: { children: React.ReactNode }) {
+  const { data: viewerId } = useViewerId()
+  const { roomData } = useRoomData()
+  const { activePlayers: activePlayerIds, players } = useGameMode()
+
+  // Get active players as array (keep Set iteration order to match UI display)
+  const activePlayers = Array.from(activePlayerIds)
+
+  const initialState = useMemo(() => ({
+    difficulty: 1,
+    timer: 30,
+    gamePhase: 'setup' as const,
+    activePlayers: [],
+    playerMetadata: {},
+    currentPlayer: '',
+    score: {},
+  }), [])
+
+  const { state, sendMove, exitSession, lastError, clearError } =
+    useArcadeSession<MyGameState>({
+      userId: viewerId || '',
+      roomId: roomData?.id,
+      initialState,
+      applyMove: (state, move) => state, // Server handles all updates
+    })
+
+  const startGame = useCallback(() => {
+    const playerMetadata = buildPlayerMetadata(activePlayers, {}, players, viewerId)
+
+    sendMove({
+      type: 'START_GAME',
+      playerId: activePlayers[0],
+      userId: viewerId || '',
+      data: { activePlayers, playerMetadata },
+    })
+  }, [activePlayers, players, viewerId, sendMove])
+
+  const makeMove = useCallback((data: any) => {
+    sendMove({
+      type: 'MAKE_MOVE',
+      playerId: state.currentPlayer,
+      userId: viewerId || '',
+      data,
+    })
+  }, [state.currentPlayer, viewerId, sendMove])
+
+  return (
+    <MyGameContext.Provider value={{
+      state,
+      lastError,
+      startGame,
+      makeMove,
+      clearError,
+      exitSession,
+    }}>
+      {children}
+    </MyGameContext.Provider>
+  )
+}
+```
+
+### Step 5: Create Game Component (`GameComponent.tsx`)
+
+```typescript
+'use client'
+
+import { useRouter } from 'next/navigation'
+import { PageWithNav } from '@/components/PageWithNav'
+import { useMyGame } from '../Provider'
+import { SetupPhase } from './SetupPhase'
+import { PlayingPhase } from './PlayingPhase'
+import { ResultsPhase } from './ResultsPhase'
+
+export function GameComponent() {
+  const router = useRouter()
+  const { state, exitSession } = useMyGame()
+
+  // Determine whose turn it is for the turn indicator
+  const currentPlayerId = state.gamePhase === 'playing' ? state.currentPlayer : undefined
+
+  return (
+    <PageWithNav
+      navTitle="My Game"
+      navEmoji="🎮"
+      emphasizePlayerSelection={state.gamePhase === 'setup'}
+      currentPlayerId={currentPlayerId}
+      playerScores={state.score}
+      onExitSession={() => {
+        exitSession()
+        router.push('/arcade')
+      }}
+    >
+      {state.gamePhase === 'setup' && <SetupPhase />}
+      {state.gamePhase === 'playing' && <PlayingPhase />}
+      {state.gamePhase === 'results' && <ResultsPhase />}
+    </PageWithNav>
+  )
+}
+```
+
+### Step 6: Define Game (`index.ts`)
+
+```typescript
+import { defineGame } from '@/lib/arcade/game-sdk'
+import type { GameManifest } from '@/lib/arcade/game-sdk'
+import { GameComponent } from './components/GameComponent'
+import { MyGameProvider } from './Provider'
+import type { MyGameConfig, MyGameMove, MyGameState } from './types'
+import { myGameValidator } from './Validator'
+
+const manifest: GameManifest = {
+  name: 'my-game',
+  displayName: 'My Awesome Game',
+  icon: '🎮',
+  description: 'A fun multiplayer game',
+  longDescription: 'Detailed description of gameplay...',
+  maxPlayers: 4,
+  difficulty: 'Beginner',
+  chips: ['👥 Multiplayer', '🎲 Turn-Based'],
+  color: 'blue',
+  gradient: 'linear-gradient(135deg, #bfdbfe, #93c5fd)',
+  borderColor: 'blue.200',
+  available: true,
+}
+
+const defaultConfig: MyGameConfig = {
+  difficulty: 1,
+  timer: 30,
+}
+
+export const myGame = defineGame<MyGameConfig, MyGameState, MyGameMove>({
+  manifest,
+  Provider: MyGameProvider,
+  GameComponent,
+  validator: myGameValidator,
+  defaultConfig,
+})
+```
+
+### Step 7: Register Game
+
+#### 7a. Register Validator (Server-Side)
+
+Add your validator to the unified registry in `src/lib/arcade/validators.ts`:
+
+```typescript
+import { myGameValidator } from '@/arcade-games/my-game/Validator'
+
+export const validatorRegistry = {
+  matching: matchingGameValidator,
+  'memory-quiz': memoryQuizGameValidator,
+  'number-guesser': numberGuesserValidator,
+  'my-game': myGameValidator,  // Add your game here!
+  // GameName type will auto-update from these keys
+} as const
+```
+
+**Why**: The validator registry is isomorphic (runs on both client and server) and serves as the single source of truth for all game validators. Adding your validator here automatically:
+- Makes it available for server-side move validation
+- Updates the `GameName` type (no manual type updates needed!)
+- Enables your game for multiplayer rooms
+
+#### 7b. Register Game Definition (Client-Side)
+
+Add to `src/lib/arcade/game-registry.ts`:
+
+```typescript
+import { myGame } from '@/arcade-games/my-game'
+
+registerGame(myGame)
+```
+
+**Why**: The game registry is client-only and connects your game's UI components (Provider, GameComponent) with the arcade system. Registration happens on client init and verifies that your validator is also registered server-side.
+
+**Verification**: When you register a game, the registry will warn you if:
+- ⚠️  The validator is missing from `validators.ts`
+- ⚠️  The validator instance doesn't match (different imports)
+
+**Important**: Both steps are required for a working game. The validator registry handles server logic, while the game registry handles client UI.
+
+---
+
+## File Structure
+
+```
+src/arcade-games/my-game/
+├── index.ts                 # Game definition and export
+├── Validator.ts             # Server-side move validation
+├── Provider.tsx             # Client state management
+├── GameComponent.tsx        # Main UI wrapper
+├── types.ts                 # TypeScript type definitions
+└── components/
+    ├── SetupPhase.tsx       # Setup/lobby UI
+    ├── PlayingPhase.tsx     # Main gameplay UI
+    └── ResultsPhase.tsx     # End game/scores UI
+```
+
+### File Responsibilities
+
+| File | Purpose | Runs On |
+|------|---------|---------|
+| `index.ts` | Game registration | Both |
+| `Validator.ts` | Move validation, game logic | **Server only** |
+| `Provider.tsx` | State management, API calls | Client only |
+| `GameComponent.tsx` | Navigation, phase routing | Client only |
+| `types.ts` | Shared type definitions | Both |
+| `components/*` | UI for each game phase | Client only |
+
+---
+
+## Examples
+
+### Number Guesser (Turn-Based)
+
+See `src/arcade-games/number-guesser/` for a complete example of:
+- Turn-based gameplay (chooser → guessers)
+- Player rotation logic
+- Round management
+- Score tracking
+- Hot/cold feedback system
+- Error handling and user feedback
+
+**Key Patterns:**
+- Setting `currentPlayerId` for turn indicators
+- Rotating turns in validator
+- Handling round vs. game completion
+- Type coercion for JSON-serialized numbers
+
+---
+
+## Best Practices
+
+### 1. Player Ordering Consistency
+
+**Problem**: Sets don't guarantee order, causing mismatch between UI and game logic.
+
+**Solution**: Use `Array.from(activePlayerIds)` without sorting in both UI and game logic.
+
+```typescript
+// In Provider
+const activePlayers = Array.from(activePlayerIds) // NO .sort()
+
+// In Validator
+const newState = {
+  ...state,
+  currentPlayer: activePlayers[0], // First in Set order = first in UI
+}
+```
+
+### 2. Type Coercion for Numbers
+
+**Problem**: WebSocket JSON serialization converts numbers to strings.
+
+**Solution**: Explicitly coerce in validator:
+
+```typescript
+validateMove(state: MyGameState, move: MyGameMove): ValidationResult {
+  switch (move.type) {
+    case 'MAKE_GUESS':
+      return this.validateGuess(state, Number(move.data.guess)) // Coerce!
+  }
+}
+```
+
+### 3. Error Feedback
+
+**Problem**: Users don't see why their moves were rejected.
+
+**Solution**: Use `lastError` from `useArcadeSession`:
+
+```typescript
+const { state, lastError, clearError } = useArcadeSession(...)
+
+// Auto-dismiss after 5 seconds
+useEffect(() => {
+  if (lastError) {
+    const timeout = setTimeout(() => clearError(), 5000)
+    return () => clearTimeout(timeout)
+  }
+}, [lastError, clearError])
+
+// Show in UI
+{lastError && (
+  <div className="error-banner">
+    <div>⚠️ Move Rejected</div>
+    <div>{lastError}</div>
+    <button onClick={clearError}>Dismiss</button>
+  </div>
+)}
+```
+
+### 4. Turn Indicators
+
+**Problem**: Players don't know whose turn it is.
+
+**Solution**: Pass `currentPlayerId` to `PageWithNav`:
+
+```typescript
+<PageWithNav
+  currentPlayerId={state.currentPlayer}
+  playerScores={state.scores}
+>
+```
+
+### 5. Server-Only Logic
+
+**Problem**: Client can cheat by modifying local state.
+
+**Solution**: All game logic in validator, client uses `applyMove: (state) => state`:
+
+```typescript
+// ❌ BAD: Client calculates winner
+const { state, sendMove } = useArcadeSession({
+  applyMove: (state, move) => {
+    if (move.type === 'SCORE') {
+      return { ...state, winner: calculateWinner(state) } // Cheatable!
+    }
+  }
+})
+
+// ✅ GOOD: Server calculates everything
+const { state, sendMove } = useArcadeSession({
+  applyMove: (state, move) => state // Client just waits for server
+})
+```
+
+### 6. Phase Management
+
+Use discriminated union for type-safe phase rendering:
+
+```typescript
+type GamePhase = 'setup' | 'playing' | 'results'
+
+interface MyGameState {
+  gamePhase: GamePhase
+  // ...
+}
+
+// In GameComponent
+{state.gamePhase === 'setup' && <SetupPhase />}
+{state.gamePhase === 'playing' && <PlayingPhase />}
+{state.gamePhase === 'results' && <ResultsPhase />}
+```
+
+---
+
+## Troubleshooting
+
+### "Player not found" errors
+
+**Cause**: Player IDs from `useGameMode()` don't match server state.
+
+**Fix**: Always use `buildPlayerMetadata()` helper:
+
+```typescript
+const playerMetadata = buildPlayerMetadata(activePlayers, {}, players, viewerId)
+```
+
+### Turn indicator not showing
+
+**Cause**: `currentPlayerId` not passed or doesn't match player IDs in UI.
+
+**Fix**: Verify player order matches between game state and `activePlayerIds`:
+
+```typescript
+// Both should use same source without sorting
+const activePlayers = Array.from(activePlayerIds) // Provider
+const activePlayerList = Array.from(activePlayers) // PageWithNav
+```
+
+### Moves rejected with type errors
+
+**Cause**: JSON serialization converts numbers to strings.
+
+**Fix**: Add `Number()` coercion in validator:
+
+```typescript
+case 'SET_VALUE':
+  return this.validateValue(state, Number(move.data.value))
+```
+
+### State not syncing across clients
+
+**Cause**: Not using `useArcadeSession` correctly.
+
+**Fix**: Ensure `roomId` is passed:
+
+```typescript
+const { state, sendMove } = useArcadeSession({
+  userId: viewerId || '',
+  roomId: roomData?.id, // Required for room sync!
+  initialState,
+  applyMove: (state) => state,
+})
+```
+
+### Game not appearing in selector
+
+**Cause**: Not registered or `available: false`.
+
+**Fix**:
+1. Add to `game-registry.ts`: `registerGame(myGame)`
+2. Set `available: true` in manifest
+3. Verify no console errors on import
+
+### Config changes not taking effect
+
+**Cause**: State sync timing - validator uses old state while config is being updated.
+
+**Context**: When you change game config (e.g., min/max numbers), there's a brief window where:
+1. Client updates config in database
+2. Config change hasn't propagated to server state yet
+3. Moves are validated against old state
+
+**Fix**: Ensure config changes trigger state reset or are applied atomically:
+
+```typescript
+// When changing config, also update initialState
+const setConfig = useCallback((field, value) => {
+  sendMove({ type: 'SET_CONFIG', data: { field, value } })
+
+  // Persist to database for next session
+  if (roomData?.id) {
+    updateGameConfig({
+      roomId: roomData.id,
+      gameConfig: {
+        ...roomData.gameConfig,
+        'my-game': { ...currentConfig, [field]: value }
+      }
+    })
+  }
+}, [sendMove, updateGameConfig, roomData])
+```
+
+**Best Practice**: Make config changes only during setup phase, before game starts.
+
+### Debugging validation errors
+
+**Problem**: Moves rejected but unclear why (especially type-related issues).
+
+**Solution**: Add debug logging in validator:
+
+```typescript
+private validateGuess(state: State, guess: number): ValidationResult {
+  // Debug logging
+  console.log('[MyGame] Validating guess:', {
+    guess,
+    guessType: typeof guess,           // Check if it's a string!
+    min: state.minNumber,
+    minType: typeof state.minNumber,
+    max: state.maxNumber,
+    maxType: typeof state.maxNumber,
+  })
+
+  if (guess < state.minNumber || guess > state.maxNumber) {
+    return { valid: false, error: `Guess must be between ${state.minNumber} and ${state.maxNumber}` }
+  }
+
+  // ... rest of validation
+}
+```
+
+**What to check:**
+1. **Browser console**: Look for `[ArcadeSession] Move rejected by server:` messages
+2. **Server logs**: Check validator console.log output for types and values
+3. **Type mismatches**: Numbers becoming strings is the #1 issue
+4. **State sync**: Is the validator using the state you expect?
+
+**Common debugging workflow:**
+1. Move rejected → Check browser console for error message
+2. Error unclear → Add console.log to validator
+3. Restart server → See debug output when move is made
+4. Compare expected vs. actual values/types
+5. Add `Number()` coercion if types don't match
+
+---
+
+## Resources
+
+- **Game SDK**: `src/lib/arcade/game-sdk/`
+- **Registry**: `src/lib/arcade/game-registry.ts`
+- **Example Game**: `src/arcade-games/number-guesser/`
+- **Validation Types**: `src/lib/arcade/validation/types.ts`
+
+---
+
+## FAQ
+
+**Q: Can I use external libraries in my game?**
+A: Yes, but install them in the workspace package.json. Games should be self-contained.
+
+**Q: How do I add game configuration that persists?**
+A: Use `useUpdateGameConfig()` to save to room:
+
+```typescript
+const { mutate: updateGameConfig } = useUpdateGameConfig()
+
+updateGameConfig({
+  roomId: roomData.id,
+  gameConfig: {
+    ...roomData.gameConfig,
+    'my-game': { difficulty: 5 }
+  }
+})
+```
+
+**Q: Can I have asymmetric player roles?**
+A: Yes! See Number Guesser's chooser/guesser pattern.
+
+**Q: How do I handle real-time timers?**
+A: Store `startTime` in state, use client-side countdown, server validates elapsed time.
+
+**Q: What's the difference between `playerId` and `userId`?**
+A: `userId` is the user account, `playerId` is the avatar/character in the game. One user can control multiple players.

apps/web/src/arcade-games/math-sprint/Provider.tsx

@@ -0,0 +1,198 @@
+/**
+ * Math Sprint Provider
+ *
+ * Context provider for Math Sprint game state management.
+ * Demonstrates free-for-all gameplay with TEAM_MOVE pattern.
+ */
+
+'use client'
+
+import { createContext, useCallback, useContext, useMemo, type ReactNode } from 'react'
+import {
+  buildPlayerMetadata,
+  useArcadeSession,
+  useGameMode,
+  useRoomData,
+  useUpdateGameConfig,
+  useViewerId,
+} from '@/lib/arcade/game-sdk'
+import { TEAM_MOVE } from '@/lib/arcade/validation/types'
+import type { Difficulty, MathSprintState } from './types'
+
+/**
+ * Context value provided to child components
+ */
+interface MathSprintContextValue {
+  state: MathSprintState
+  lastError: string | null
+  startGame: () => void
+  submitAnswer: (answer: number) => void
+  nextQuestion: () => void
+  resetGame: () => void
+  setConfig: (field: 'difficulty' | 'questionsPerRound' | 'timePerQuestion', value: any) => void
+  clearError: () => void
+  exitSession: () => void
+}
+
+const MathSprintContext = createContext<MathSprintContextValue | null>(null)
+
+/**
+ * Hook to access Math Sprint context
+ */
+export function useMathSprint() {
+  const context = useContext(MathSprintContext)
+  if (!context) {
+    throw new Error('useMathSprint must be used within MathSprintProvider')
+  }
+  return context
+}
+
+/**
+ * Math Sprint Provider Component
+ */
+export function MathSprintProvider({ children }: { children: ReactNode }) {
+  const { data: viewerId } = useViewerId()
+  const { roomData } = useRoomData()
+  const { activePlayers: activePlayerIds, players } = useGameMode()
+  const { mutate: updateGameConfig } = useUpdateGameConfig()
+
+  // Get active players as array (keep Set iteration order)
+  const activePlayers = Array.from(activePlayerIds)
+
+  // Merge saved config from room with defaults
+  const gameConfig = useMemo(() => {
+    const allGameConfigs = roomData?.gameConfig as Record<string, unknown> | null | undefined
+    const savedConfig = allGameConfigs?.['math-sprint'] as Record<string, unknown> | undefined
+    return {
+      difficulty: (savedConfig?.difficulty as Difficulty) || 'medium',
+      questionsPerRound: (savedConfig?.questionsPerRound as number) || 10,
+      timePerQuestion: (savedConfig?.timePerQuestion as number) || 30,
+    }
+  }, [roomData?.gameConfig])
+
+  // Initial state with merged config
+  const initialState = useMemo<MathSprintState>(
+    () => ({
+      gamePhase: 'setup',
+      activePlayers: [],
+      playerMetadata: {},
+      difficulty: gameConfig.difficulty,
+      questionsPerRound: gameConfig.questionsPerRound,
+      timePerQuestion: gameConfig.timePerQuestion,
+      currentQuestionIndex: 0,
+      questions: [],
+      scores: {},
+      correctAnswersCount: {},
+      answers: [],
+      questionStartTime: 0,
+      questionAnswered: false,
+      winnerId: null,
+    }),
+    [gameConfig]
+  )
+
+  // Arcade session integration
+  const { state, sendMove, exitSession, lastError, clearError } =
+    useArcadeSession<MathSprintState>({
+      userId: viewerId || '',
+      roomId: roomData?.id,
+      initialState,
+      applyMove: (state) => state, // Server handles all state updates
+    })
+
+  // Action: Start game
+  const startGame = useCallback(() => {
+    const playerMetadata = buildPlayerMetadata(activePlayers, {}, players, viewerId || undefined)
+
+    sendMove({
+      type: 'START_GAME',
+      playerId: TEAM_MOVE, // Free-for-all: no specific turn owner
+      userId: viewerId || '',
+      data: { activePlayers, playerMetadata },
+    })
+  }, [activePlayers, players, viewerId, sendMove])
+
+  // Action: Submit answer
+  const submitAnswer = useCallback(
+    (answer: number) => {
+      // Find this user's player ID from game state
+      const myPlayerId = state.activePlayers.find((pid) => {
+        return state.playerMetadata[pid]?.userId === viewerId
+      })
+
+      if (!myPlayerId) {
+        console.error('[MathSprint] No player found for current user')
+        return
+      }
+
+      sendMove({
+        type: 'SUBMIT_ANSWER',
+        playerId: myPlayerId, // Specific player answering
+        userId: viewerId || '',
+        data: { answer },
+      })
+    },
+    [state.activePlayers, state.playerMetadata, viewerId, sendMove]
+  )
+
+  // Action: Next question
+  const nextQuestion = useCallback(() => {
+    sendMove({
+      type: 'NEXT_QUESTION',
+      playerId: TEAM_MOVE, // Any player can advance
+      userId: viewerId || '',
+      data: {},
+    })
+  }, [viewerId, sendMove])
+
+  // Action: Reset game
+  const resetGame = useCallback(() => {
+    sendMove({
+      type: 'RESET_GAME',
+      playerId: TEAM_MOVE,
+      userId: viewerId || '',
+      data: {},
+    })
+  }, [viewerId, sendMove])
+
+  // Action: Set config
+  const setConfig = useCallback(
+    (field: 'difficulty' | 'questionsPerRound' | 'timePerQuestion', value: any) => {
+      sendMove({
+        type: 'SET_CONFIG',
+        playerId: TEAM_MOVE,
+        userId: viewerId || '',
+        data: { field, value },
+      })
+
+      // Persist to database for next session
+      if (roomData?.id) {
+        updateGameConfig({
+          roomId: roomData.id,
+          gameConfig: {
+            ...roomData.gameConfig,
+            'math-sprint': {
+              ...(roomData.gameConfig?.['math-sprint'] || {}),
+              [field]: value,
+            },
+          },
+        })
+      }
+    },
+    [viewerId, sendMove, updateGameConfig, roomData]
+  )
+
+  const contextValue: MathSprintContextValue = {
+    state,
+    lastError,
+    startGame,
+    submitAnswer,
+    nextQuestion,
+    resetGame,
+    setConfig,
+    clearError,
+    exitSession,
+  }
+
+  return <MathSprintContext.Provider value={contextValue}>{children}</MathSprintContext.Provider>
+}

apps/web/src/arcade-games/math-sprint/Validator.ts

@@ -0,0 +1,340 @@
+/**
+ * Math Sprint Validator
+ *
+ * Server-side validation for Math Sprint game.
+ * Generates questions, validates answers, awards points.
+ */
+
+import type { GameValidator, ValidationResult } from '@/lib/arcade/game-sdk'
+import { TEAM_MOVE } from '@/lib/arcade/validation/types'
+import type {
+  Difficulty,
+  MathSprintConfig,
+  MathSprintMove,
+  MathSprintState,
+  Operation,
+  Question,
+} from './types'
+
+export class MathSprintValidator
+  implements GameValidator<MathSprintState, MathSprintMove>
+{
+  /**
+   * Validate a game move
+   */
+  validateMove(
+    state: MathSprintState,
+    move: MathSprintMove,
+    context?: { userId?: string }
+  ): ValidationResult {
+    switch (move.type) {
+      case 'START_GAME':
+        return this.validateStartGame(state, move.data.activePlayers, move.data.playerMetadata)
+
+      case 'SUBMIT_ANSWER':
+        return this.validateSubmitAnswer(
+          state,
+          move.playerId,
+          Number(move.data.answer),
+          move.timestamp
+        )
+
+      case 'NEXT_QUESTION':
+        return this.validateNextQuestion(state)
+
+      case 'RESET_GAME':
+        return this.validateResetGame(state)
+
+      case 'SET_CONFIG':
+        return this.validateSetConfig(state, move.data.field, move.data.value)
+
+      default:
+        return { valid: false, error: 'Unknown move type' }
+    }
+  }
+
+  /**
+   * Check if game is complete
+   */
+  isGameComplete(state: MathSprintState): boolean {
+    return state.gamePhase === 'results'
+  }
+
+  /**
+   * Get initial state for new game
+   */
+  getInitialState(config: unknown): MathSprintState {
+    const { difficulty, questionsPerRound, timePerQuestion } = config as MathSprintConfig
+
+    return {
+      gamePhase: 'setup',
+      activePlayers: [],
+      playerMetadata: {},
+      difficulty: difficulty || 'medium',
+      questionsPerRound: questionsPerRound || 10,
+      timePerQuestion: timePerQuestion || 30,
+      currentQuestionIndex: 0,
+      questions: [],
+      scores: {},
+      correctAnswersCount: {},
+      answers: [],
+      questionStartTime: 0,
+      questionAnswered: false,
+      winnerId: null,
+    }
+  }
+
+  // ============================================================================
+  // Validation Methods
+  // ============================================================================
+
+  private validateStartGame(
+    state: MathSprintState,
+    activePlayers: string[],
+    playerMetadata: Record<string, any>
+  ): ValidationResult {
+    if (state.gamePhase !== 'setup') {
+      return { valid: false, error: 'Game already started' }
+    }
+
+    if (activePlayers.length < 2) {
+      return { valid: false, error: 'Need at least 2 players' }
+    }
+
+    // Generate questions
+    const questions = this.generateQuestions(state.difficulty, state.questionsPerRound)
+
+    const newState: MathSprintState = {
+      ...state,
+      gamePhase: 'playing',
+      activePlayers,
+      playerMetadata,
+      questions,
+      currentQuestionIndex: 0,
+      scores: activePlayers.reduce((acc, p) => ({ ...acc, [p]: 0 }), {}),
+      correctAnswersCount: activePlayers.reduce((acc, p) => ({ ...acc, [p]: 0 }), {}),
+      answers: [],
+      questionStartTime: Date.now(),
+      questionAnswered: false,
+      winnerId: null,
+    }
+
+    return { valid: true, newState }
+  }
+
+  private validateSubmitAnswer(
+    state: MathSprintState,
+    playerId: string,
+    answer: number,
+    timestamp: number
+  ): ValidationResult {
+    if (state.gamePhase !== 'playing') {
+      return { valid: false, error: 'Game not in progress' }
+    }
+
+    if (!state.activePlayers.includes(playerId)) {
+      return { valid: false, error: 'Player not in game' }
+    }
+
+    if (state.questionAnswered) {
+      return { valid: false, error: 'Question already answered correctly' }
+    }
+
+    // Check if player already answered this question
+    const alreadyAnswered = state.answers.some((a) => a.playerId === playerId)
+    if (alreadyAnswered) {
+      return { valid: false, error: 'You already answered this question' }
+    }
+
+    const currentQuestion = state.questions[state.currentQuestionIndex]
+    const correct = answer === currentQuestion.correctAnswer
+
+    const answerRecord = {
+      playerId,
+      answer,
+      timestamp,
+      correct,
+    }
+
+    const newAnswers = [...state.answers, answerRecord]
+    let newState = { ...state, answers: newAnswers }
+
+    // If correct, award points and mark question as answered
+    if (correct) {
+      newState = {
+        ...newState,
+        questionAnswered: true,
+        winnerId: playerId,
+        scores: {
+          ...state.scores,
+          [playerId]: state.scores[playerId] + 10,
+        },
+        correctAnswersCount: {
+          ...state.correctAnswersCount,
+          [playerId]: state.correctAnswersCount[playerId] + 1,
+        },
+      }
+    }
+
+    return { valid: true, newState }
+  }
+
+  private validateNextQuestion(state: MathSprintState): ValidationResult {
+    if (state.gamePhase !== 'playing') {
+      return { valid: false, error: 'Game not in progress' }
+    }
+
+    if (!state.questionAnswered) {
+      return { valid: false, error: 'Current question not answered yet' }
+    }
+
+    const isLastQuestion = state.currentQuestionIndex >= state.questions.length - 1
+
+    if (isLastQuestion) {
+      // Game complete, go to results
+      const newState: MathSprintState = {
+        ...state,
+        gamePhase: 'results',
+      }
+      return { valid: true, newState }
+    }
+
+    // Move to next question
+    const newState: MathSprintState = {
+      ...state,
+      currentQuestionIndex: state.currentQuestionIndex + 1,
+      answers: [],
+      questionStartTime: Date.now(),
+      questionAnswered: false,
+      winnerId: null,
+    }
+
+    return { valid: true, newState }
+  }
+
+  private validateResetGame(state: MathSprintState): ValidationResult {
+    const newState = this.getInitialState({
+      difficulty: state.difficulty,
+      questionsPerRound: state.questionsPerRound,
+      timePerQuestion: state.timePerQuestion,
+    })
+
+    return { valid: true, newState }
+  }
+
+  private validateSetConfig(
+    state: MathSprintState,
+    field: string,
+    value: any
+  ): ValidationResult {
+    if (state.gamePhase !== 'setup') {
+      return { valid: false, error: 'Cannot change config during game' }
+    }
+
+    const newState = {
+      ...state,
+      [field]: value,
+    }
+
+    return { valid: true, newState }
+  }
+
+  // ============================================================================
+  // Question Generation
+  // ============================================================================
+
+  private generateQuestions(difficulty: Difficulty, count: number): Question[] {
+    const questions: Question[] = []
+
+    for (let i = 0; i < count; i++) {
+      const operation = this.randomOperation()
+      const question = this.generateQuestion(difficulty, operation, `q-${i}`)
+      questions.push(question)
+    }
+
+    return questions
+  }
+
+  private generateQuestion(
+    difficulty: Difficulty,
+    operation: Operation,
+    id: string
+  ): Question {
+    let operand1: number
+    let operand2: number
+    let correctAnswer: number
+
+    switch (difficulty) {
+      case 'easy':
+        operand1 = this.randomInt(1, 10)
+        operand2 = this.randomInt(1, 10)
+        break
+      case 'medium':
+        operand1 = this.randomInt(10, 50)
+        operand2 = this.randomInt(1, 20)
+        break
+      case 'hard':
+        operand1 = this.randomInt(10, 100)
+        operand2 = this.randomInt(10, 50)
+        break
+    }
+
+    switch (operation) {
+      case 'addition':
+        correctAnswer = operand1 + operand2
+        break
+      case 'subtraction':
+        // Ensure positive result
+        if (operand1 < operand2) {
+          ;[operand1, operand2] = [operand2, operand1]
+        }
+        correctAnswer = operand1 - operand2
+        break
+      case 'multiplication':
+        // Smaller numbers for multiplication
+        if (difficulty === 'hard') {
+          operand1 = this.randomInt(2, 20)
+          operand2 = this.randomInt(2, 12)
+        } else {
+          operand1 = this.randomInt(2, 10)
+          operand2 = this.randomInt(2, 10)
+        }
+        correctAnswer = operand1 * operand2
+        break
+    }
+
+    const operationSymbol = this.getOperationSymbol(operation)
+    const displayText = `${operand1} ${operationSymbol} ${operand2} = ?`
+
+    return {
+      id,
+      operand1,
+      operand2,
+      operation,
+      correctAnswer,
+      displayText,
+    }
+  }
+
+  private randomOperation(): Operation {
+    const operations: Operation[] = ['addition', 'subtraction', 'multiplication']
+    return operations[Math.floor(Math.random() * operations.length)]
+  }
+
+  private randomInt(min: number, max: number): number {
+    return Math.floor(Math.random() * (max - min + 1)) + min
+  }
+
+  private getOperationSymbol(operation: Operation): string {
+    switch (operation) {
+      case 'addition':
+        return '+'
+      case 'subtraction':
+        return '−'
+      case 'multiplication':
+        return '×'
+    }
+  }
+}
+
+export const mathSprintValidator = new MathSprintValidator()

apps/web/src/arcade-games/math-sprint/components/GameComponent.tsx

@@ -0,0 +1,40 @@
+/**
+ * Math Sprint - Game Component
+ *
+ * Main wrapper component with navigation and phase routing.
+ */
+
+'use client'
+
+import { useRouter } from 'next/navigation'
+import { PageWithNav } from '@/components/PageWithNav'
+import { useMathSprint } from '../Provider'
+import { PlayingPhase } from './PlayingPhase'
+import { ResultsPhase } from './ResultsPhase'
+import { SetupPhase } from './SetupPhase'
+
+export function GameComponent() {
+  const router = useRouter()
+  const { state, exitSession, resetGame } = useMathSprint()
+
+  return (
+    <PageWithNav
+      navTitle="Math Sprint"
+      navEmoji="🧮"
+      emphasizePlayerSelection={state.gamePhase === 'setup'}
+      // No currentPlayerId - free-for-all game, everyone can act simultaneously
+      playerScores={state.scores}
+      onExitSession={() => {
+        exitSession?.()
+        router.push('/arcade')
+      }}
+      onNewGame={() => {
+        resetGame()
+      }}
+    >
+      {state.gamePhase === 'setup' && <SetupPhase />}
+      {state.gamePhase === 'playing' && <PlayingPhase />}
+      {state.gamePhase === 'results' && <ResultsPhase />}
+    </PageWithNav>
+  )
+}

apps/web/src/arcade-games/math-sprint/components/PlayingPhase.tsx

@@ -0,0 +1,347 @@
+/**
+ * Math Sprint - Playing Phase
+ *
+ * Main gameplay: show question, accept answers, show feedback.
+ */
+
+'use client'
+
+import { useEffect, useState } from 'react'
+import { useViewerId } from '@/lib/arcade/game-sdk'
+import { css } from '../../../../styled-system/css'
+import { useMathSprint } from '../Provider'
+
+export function PlayingPhase() {
+  const { state, submitAnswer, nextQuestion, lastError, clearError } = useMathSprint()
+  const { data: viewerId } = useViewerId()
+  const [inputValue, setInputValue] = useState('')
+
+  const currentQuestion = state.questions[state.currentQuestionIndex]
+  const progress = `${state.currentQuestionIndex + 1} / ${state.questions.length}`
+
+  // Find if current user answered
+  const myPlayerId = Object.keys(state.playerMetadata).find(
+    (pid) => state.playerMetadata[pid]?.userId === viewerId
+  )
+  const myAnswer = state.answers.find((a) => a.playerId === myPlayerId)
+
+  // Auto-clear error after 3 seconds
+  useEffect(() => {
+    if (lastError) {
+      const timeout = setTimeout(() => clearError(), 3000)
+      return () => clearTimeout(timeout)
+    }
+  }, [lastError, clearError])
+
+  // Clear input after question changes
+  useEffect(() => {
+    setInputValue('')
+  }, [state.currentQuestionIndex])
+
+  const handleSubmit = () => {
+    const answer = Number.parseInt(inputValue, 10)
+    if (Number.isNaN(answer)) return
+
+    submitAnswer(answer)
+  }
+
+  const handleKeyDown = (e: React.KeyboardEvent) => {
+    if (e.key === 'Enter') {
+      handleSubmit()
+    }
+  }
+
+  return (
+    <div
+      className={css({
+        display: 'flex',
+        flexDirection: 'column',
+        gap: '24px',
+        maxWidth: '700px',
+        margin: '0 auto',
+        padding: '32px 20px',
+      })}
+    >
+      {/* Progress Bar */}
+      <div
+        className={css({
+          background: 'white',
+          border: '1px solid',
+          borderColor: 'gray.200',
+          borderRadius: '12px',
+          padding: '16px',
+        })}
+      >
+        <div
+          className={css({
+            display: 'flex',
+            justifyContent: 'space-between',
+            alignItems: 'center',
+            marginBottom: '8px',
+          })}
+        >
+          <span className={css({ fontSize: 'sm', fontWeight: 'semibold' })}>Question {progress}</span>
+          <span className={css({ fontSize: 'sm', color: 'gray.600' })}>
+            {state.difficulty.charAt(0).toUpperCase() + state.difficulty.slice(1)}
+          </span>
+        </div>
+        <div
+          className={css({
+            background: 'gray.200',
+            height: '8px',
+            borderRadius: '4px',
+            overflow: 'hidden',
+          })}
+        >
+          <div
+            className={css({
+              background: 'linear-gradient(90deg, #a78bfa, #8b5cf6)',
+              height: '100%',
+              borderRadius: '4px',
+              transition: 'width 0.3s',
+            })}
+            style={{
+              width: `${((state.currentQuestionIndex + 1) / state.questions.length) * 100}%`,
+            }}
+          />
+        </div>
+      </div>
+
+      {/* Error Banner */}
+      {lastError && (
+        <div
+          className={css({
+            background: 'linear-gradient(135deg, #fef2f2, #fee2e2)',
+            border: '2px solid',
+            borderColor: 'red.300',
+            borderRadius: '12px',
+            padding: '12px 16px',
+            display: 'flex',
+            alignItems: 'center',
+            justifyContent: 'space-between',
+          })}
+        >
+          <div className={css({ display: 'flex', alignItems: 'center', gap: '8px' })}>
+            <span>⚠️</span>
+            <span className={css({ fontSize: 'sm', color: 'red.700' })}>{lastError}</span>
+          </div>
+          <button
+            type="button"
+            onClick={clearError}
+            className={css({
+              fontSize: 'xs',
+              padding: '4px 8px',
+              background: 'red.100',
+              border: 'none',
+              borderRadius: '4px',
+              cursor: 'pointer',
+              _hover: { background: 'red.200' },
+            })}
+          >
+            Dismiss
+          </button>
+        </div>
+      )}
+
+      {/* Question Display */}
+      <div
+        className={css({
+          background: 'linear-gradient(135deg, #ede9fe, #ddd6fe)',
+          border: '2px solid',
+          borderColor: 'purple.300',
+          borderRadius: '16px',
+          padding: '48px',
+          textAlign: 'center',
+        })}
+      >
+        <div
+          className={css({
+            fontSize: '4xl',
+            fontWeight: 'bold',
+            color: 'purple.700',
+            fontFamily: 'monospace',
+          })}
+        >
+          {currentQuestion.displayText}
+        </div>
+      </div>
+
+      {/* Answer Input */}
+      {!state.questionAnswered && (
+        <div
+          className={css({
+            background: 'white',
+            border: '2px solid',
+            borderColor: myAnswer ? 'gray.300' : 'purple.500',
+            borderRadius: '12px',
+            padding: '24px',
+          })}
+        >
+          {myAnswer ? (
+            <div className={css({ textAlign: 'center' })}>
+              <div
+                className={css({
+                  fontSize: 'lg',
+                  color: 'gray.600',
+                  marginBottom: '8px',
+                })}
+              >
+                Your answer: <strong>{myAnswer.answer}</strong>
+              </div>
+              <div className={css({ fontSize: 'sm', color: 'gray.500' })}>
+                Waiting for others or correct answer...
+              </div>
+            </div>
+          ) : (
+            <div>
+              <label
+                className={css({
+                  display: 'block',
+                  fontSize: 'sm',
+                  fontWeight: 'semibold',
+                  marginBottom: '8px',
+                })}
+              >
+                Your Answer
+              </label>
+              <div className={css({ display: 'flex', gap: '12px' })}>
+                <input
+                  type="number"
+                  value={inputValue}
+                  onChange={(e) => setInputValue(e.target.value)}
+                  onKeyDown={handleKeyDown}
+                  placeholder="Type your answer..."
+                  autoFocus
+                  className={css({
+                    flex: 1,
+                    padding: '12px 16px',
+                    fontSize: 'lg',
+                    border: '2px solid',
+                    borderColor: 'gray.300',
+                    borderRadius: '8px',
+                    _focus: {
+                      outline: 'none',
+                      borderColor: 'purple.500',
+                    },
+                  })}
+                />
+                <button
+                  type="button"
+                  onClick={handleSubmit}
+                  disabled={!inputValue}
+                  className={css({
+                    padding: '12px 24px',
+                    fontSize: 'md',
+                    fontWeight: 'semibold',
+                    color: 'white',
+                    background: inputValue ? 'purple.600' : 'gray.400',
+                    border: 'none',
+                    borderRadius: '8px',
+                    cursor: inputValue ? 'pointer' : 'not-allowed',
+                    _hover: {
+                      background: inputValue ? 'purple.700' : 'gray.400',
+                    },
+                  })}
+                >
+                  Submit
+                </button>
+              </div>
+            </div>
+          )}
+        </div>
+      )}
+
+      {/* Winner Display */}
+      {state.questionAnswered && state.winnerId && (
+        <div
+          className={css({
+            background: 'linear-gradient(135deg, #d1fae5, #a7f3d0)',
+            border: '2px solid',
+            borderColor: 'green.400',
+            borderRadius: '12px',
+            padding: '24px',
+            textAlign: 'center',
+          })}
+        >
+          <div className={css({ fontSize: '3xl', marginBottom: '8px' })}>🎉</div>
+          <div className={css({ fontSize: 'lg', fontWeight: 'bold', color: 'green.700' })}>
+            {state.playerMetadata[state.winnerId]?.name || 'Someone'} got it right!
+          </div>
+          <div className={css({ fontSize: 'md', color: 'green.600', marginTop: '4px' })}>
+            Answer: {currentQuestion.correctAnswer}
+          </div>
+
+          <button
+            type="button"
+            onClick={nextQuestion}
+            className={css({
+              marginTop: '16px',
+              padding: '12px 32px',
+              fontSize: 'md',
+              fontWeight: 'semibold',
+              color: 'white',
+              background: 'green.600',
+              border: 'none',
+              borderRadius: '8px',
+              cursor: 'pointer',
+              _hover: { background: 'green.700' },
+            })}
+          >
+            Next Question →
+          </button>
+        </div>
+      )}
+
+      {/* Scoreboard */}
+      <div
+        className={css({
+          background: 'white',
+          border: '1px solid',
+          borderColor: 'gray.200',
+          borderRadius: '12px',
+          padding: '16px',
+        })}
+      >
+        <h3
+          className={css({
+            fontSize: 'sm',
+            fontWeight: 'semibold',
+            marginBottom: '12px',
+          })}
+        >
+          Scores
+        </h3>
+        <div className={css({ display: 'flex', flexDirection: 'column', gap: '8px' })}>
+          {Object.entries(state.scores)
+            .sort(([, a], [, b]) => b - a)
+            .map(([playerId, score]) => {
+              const player = state.playerMetadata[playerId]
+              return (
+                <div
+                  key={playerId}
+                  className={css({
+                    display: 'flex',
+                    justifyContent: 'space-between',
+                    alignItems: 'center',
+                    padding: '8px 12px',
+                    background: 'gray.50',
+                    borderRadius: '8px',
+                  })}
+                >
+                  <div className={css({ display: 'flex', alignItems: 'center', gap: '8px' })}>
+                    <span className={css({ fontSize: 'xl' })}>{player?.emoji}</span>
+                    <span className={css({ fontSize: 'sm', fontWeight: 'medium' })}>
+                      {player?.name}
+                    </span>
+                  </div>
+                  <span className={css({ fontSize: 'sm', fontWeight: 'bold', color: 'purple.600' })}>
+                    {score} pts
+                  </span>
+                </div>
+              )
+            })}
+        </div>
+      </div>
+    </div>
+  )
+}

apps/web/src/arcade-games/math-sprint/components/ResultsPhase.tsx

@@ -0,0 +1,194 @@
+/**
+ * Math Sprint - Results Phase
+ *
+ * Show final scores and winner.
+ */
+
+'use client'
+
+import { css } from '../../../../styled-system/css'
+import { useMathSprint } from '../Provider'
+
+export function ResultsPhase() {
+  const { state, resetGame } = useMathSprint()
+
+  // Sort players by score
+  const sortedPlayers = Object.entries(state.scores)
+    .map(([playerId, score]) => ({
+      playerId,
+      score,
+      correct: state.correctAnswersCount[playerId] || 0,
+      player: state.playerMetadata[playerId],
+    }))
+    .sort((a, b) => b.score - a.score)
+
+  const winner = sortedPlayers[0]
+
+  return (
+    <div
+      className={css({
+        display: 'flex',
+        flexDirection: 'column',
+        gap: '24px',
+        maxWidth: '600px',
+        margin: '0 auto',
+        padding: '32px 20px',
+      })}
+    >
+      {/* Winner Announcement */}
+      <div
+        className={css({
+          background: 'linear-gradient(135deg, #fef3c7, #fde68a)',
+          border: '2px solid',
+          borderColor: 'yellow.400',
+          borderRadius: '16px',
+          padding: '32px',
+          textAlign: 'center',
+        })}
+      >
+        <div className={css({ fontSize: '4xl', marginBottom: '12px' })}>🏆</div>
+        <h2
+          className={css({
+            fontSize: '2xl',
+            fontWeight: 'bold',
+            color: 'yellow.800',
+            marginBottom: '8px',
+          })}
+        >
+          {winner.player?.name} Wins!
+        </h2>
+        <div className={css({ fontSize: 'lg', color: 'yellow.700' })}>
+          {winner.score} points • {winner.correct} correct
+        </div>
+      </div>
+
+      {/* Final Scores */}
+      <div
+        className={css({
+          background: 'white',
+          border: '1px solid',
+          borderColor: 'gray.200',
+          borderRadius: '12px',
+          padding: '24px',
+        })}
+      >
+        <h3
+          className={css({
+            fontSize: 'lg',
+            fontWeight: 'semibold',
+            marginBottom: '16px',
+          })}
+        >
+          Final Scores
+        </h3>
+        <div className={css({ display: 'flex', flexDirection: 'column', gap: '12px' })}>
+          {sortedPlayers.map((item, index) => (
+            <div
+              key={item.playerId}
+              className={css({
+                display: 'flex',
+                alignItems: 'center',
+                gap: '12px',
+                padding: '16px',
+                background: index === 0 ? 'linear-gradient(135deg, #fef3c7, #fde68a)' : 'gray.50',
+                border: '1px solid',
+                borderColor: index === 0 ? 'yellow.300' : 'gray.200',
+                borderRadius: '12px',
+              })}
+            >
+              {/* Rank */}
+              <div
+                className={css({
+                  width: '32px',
+                  height: '32px',
+                  display: 'flex',
+                  alignItems: 'center',
+                  justifyContent: 'center',
+                  background: index === 0 ? 'yellow.500' : 'gray.300',
+                  color: index === 0 ? 'white' : 'gray.700',
+                  borderRadius: '50%',
+                  fontWeight: 'bold',
+                  fontSize: 'sm',
+                })}
+              >
+                {index + 1}
+              </div>
+
+              {/* Player Info */}
+              <div className={css({ flex: 1 })}>
+                <div className={css({ display: 'flex', alignItems: 'center', gap: '8px' })}>
+                  <span className={css({ fontSize: 'xl' })}>{item.player?.emoji}</span>
+                  <span className={css({ fontSize: 'md', fontWeight: 'semibold' })}>
+                    {item.player?.name}
+                  </span>
+                </div>
+                <div className={css({ fontSize: 'xs', color: 'gray.600', marginTop: '2px' })}>
+                  {item.correct} / {state.questions.length} correct
+                </div>
+              </div>
+
+              {/* Score */}
+              <div
+                className={css({
+                  fontSize: 'xl',
+                  fontWeight: 'bold',
+                  color: index === 0 ? 'yellow.700' : 'purple.600',
+                })}
+              >
+                {item.score}
+              </div>
+            </div>
+          ))}
+        </div>
+      </div>
+
+      {/* Stats */}
+      <div
+        className={css({
+          background: 'linear-gradient(135deg, #ede9fe, #ddd6fe)',
+          border: '1px solid',
+          borderColor: 'purple.300',
+          borderRadius: '12px',
+          padding: '20px',
+        })}
+      >
+        <div className={css({ display: 'grid', gridTemplateColumns: '1fr 1fr', gap: '16px' })}>
+          <div className={css({ textAlign: 'center' })}>
+            <div className={css({ fontSize: '2xl', fontWeight: 'bold', color: 'purple.700' })}>
+              {state.questions.length}
+            </div>
+            <div className={css({ fontSize: 'sm', color: 'purple.600' })}>Questions</div>
+          </div>
+          <div className={css({ textAlign: 'center' })}>
+            <div className={css({ fontSize: '2xl', fontWeight: 'bold', color: 'purple.700' })}>
+              {state.difficulty.charAt(0).toUpperCase() + state.difficulty.slice(1)}
+            </div>
+            <div className={css({ fontSize: 'sm', color: 'purple.600' })}>Difficulty</div>
+          </div>
+        </div>
+      </div>
+
+      {/* Play Again Button */}
+      <button
+        type="button"
+        onClick={resetGame}
+        className={css({
+          padding: '14px 28px',
+          fontSize: 'lg',
+          fontWeight: 'semibold',
+          color: 'white',
+          background: 'purple.600',
+          border: 'none',
+          borderRadius: '12px',
+          cursor: 'pointer',
+          transition: 'background 0.2s',
+          _hover: {
+            background: 'purple.700',
+          },
+        })}
+      >
+        Play Again
+      </button>
+    </div>
+  )
+}

apps/web/src/arcade-games/math-sprint/components/SetupPhase.tsx

@@ -0,0 +1,196 @@
+/**
+ * Math Sprint - Setup Phase
+ *
+ * Configure game settings before starting.
+ */
+
+'use client'
+
+import { css } from '../../../../styled-system/css'
+import { useMathSprint } from '../Provider'
+import type { Difficulty } from '../types'
+
+export function SetupPhase() {
+  const { state, startGame, setConfig } = useMathSprint()
+
+  const handleDifficultyChange = (difficulty: Difficulty) => {
+    setConfig('difficulty', difficulty)
+  }
+
+  const handleQuestionsChange = (questions: number) => {
+    setConfig('questionsPerRound', questions)
+  }
+
+  return (
+    <div
+      className={css({
+        display: 'flex',
+        flexDirection: 'column',
+        gap: '24px',
+        maxWidth: '600px',
+        margin: '0 auto',
+        padding: '32px 20px',
+      })}
+    >
+      {/* Game Title */}
+      <div className={css({ textAlign: 'center' })}>
+        <h1
+          className={css({
+            fontSize: '2xl',
+            fontWeight: 'bold',
+            color: 'purple.700',
+            marginBottom: '8px',
+          })}
+        >
+          🧮 Math Sprint
+        </h1>
+        <p className={css({ color: 'gray.600' })}>
+          Race to solve math problems! First correct answer wins points.
+        </p>
+      </div>
+
+      {/* Settings Card */}
+      <div
+        className={css({
+          background: 'white',
+          border: '1px solid',
+          borderColor: 'gray.200',
+          borderRadius: '12px',
+          padding: '24px',
+        })}
+      >
+        <h2
+          className={css({
+            fontSize: 'lg',
+            fontWeight: 'semibold',
+            marginBottom: '16px',
+          })}
+        >
+          Game Settings
+        </h2>
+
+        {/* Difficulty */}
+        <div className={css({ marginBottom: '20px' })}>
+          <label
+            className={css({
+              display: 'block',
+              fontSize: 'sm',
+              fontWeight: 'medium',
+              marginBottom: '8px',
+            })}
+          >
+            Difficulty
+          </label>
+          <div className={css({ display: 'flex', gap: '8px' })}>
+            {(['easy', 'medium', 'hard'] as Difficulty[]).map((diff) => (
+              <button
+                key={diff}
+                type="button"
+                onClick={() => handleDifficultyChange(diff)}
+                className={css({
+                  flex: 1,
+                  padding: '10px 16px',
+                  borderRadius: '8px',
+                  border: '2px solid',
+                  borderColor: state.difficulty === diff ? 'purple.500' : 'gray.300',
+                  background: state.difficulty === diff ? 'purple.50' : 'white',
+                  color: state.difficulty === diff ? 'purple.700' : 'gray.700',
+                  fontWeight: state.difficulty === diff ? 'semibold' : 'normal',
+                  cursor: 'pointer',
+                  transition: 'all 0.2s',
+                  _hover: {
+                    borderColor: 'purple.400',
+                  },
+                })}
+              >
+                {diff.charAt(0).toUpperCase() + diff.slice(1)}
+              </button>
+            ))}
+          </div>
+          <p className={css({ fontSize: 'xs', color: 'gray.500', marginTop: '4px' })}>
+            {state.difficulty === 'easy' && 'Numbers 1-10, simple operations'}
+            {state.difficulty === 'medium' && 'Numbers 1-50, varied operations'}
+            {state.difficulty === 'hard' && 'Numbers 1-100, harder calculations'}
+          </p>
+        </div>
+
+        {/* Questions Per Round */}
+        <div>
+          <label
+            className={css({
+              display: 'block',
+              fontSize: 'sm',
+              fontWeight: 'medium',
+              marginBottom: '8px',
+            })}
+          >
+            Questions: {state.questionsPerRound}
+          </label>
+          <input
+            type="range"
+            min="5"
+            max="20"
+            step="5"
+            value={state.questionsPerRound}
+            onChange={(e) => handleQuestionsChange(Number(e.target.value))}
+            className={css({
+              width: '100%',
+            })}
+          />
+          <div className={css({ display: 'flex', justifyContent: 'space-between', fontSize: 'xs' })}>
+            <span>5</span>
+            <span>10</span>
+            <span>15</span>
+            <span>20</span>
+          </div>
+        </div>
+      </div>
+
+      {/* Instructions */}
+      <div
+        className={css({
+          background: 'linear-gradient(135deg, #fef3c7, #fde68a)',
+          border: '1px solid',
+          borderColor: 'yellow.300',
+          borderRadius: '12px',
+          padding: '16px',
+        })}
+      >
+        <h3 className={css({ fontSize: 'sm', fontWeight: 'semibold', marginBottom: '8px' })}>
+          How to Play
+        </h3>
+        <ul className={css({ fontSize: 'sm', color: 'gray.700', paddingLeft: '20px' })}>
+          <li>Solve math problems as fast as you can</li>
+          <li>First correct answer earns 10 points</li>
+          <li>Everyone can answer at the same time</li>
+          <li>Most points wins!</li>
+        </ul>
+      </div>
+
+      {/* Start Button */}
+      <button
+        type="button"
+        onClick={startGame}
+        disabled={state.activePlayers.length < 2}
+        className={css({
+          padding: '14px 28px',
+          fontSize: 'lg',
+          fontWeight: 'semibold',
+          color: 'white',
+          background: state.activePlayers.length < 2 ? 'gray.400' : 'purple.600',
+          borderRadius: '12px',
+          border: 'none',
+          cursor: state.activePlayers.length < 2 ? 'not-allowed' : 'pointer',
+          transition: 'all 0.2s',
+          _hover: {
+            background: state.activePlayers.length < 2 ? 'gray.400' : 'purple.700',
+          },
+        })}
+      >
+        {state.activePlayers.length < 2
+          ? `Need ${2 - state.activePlayers.length} more player(s)`
+          : 'Start Game'}
+      </button>
+    </div>
+  )
+}

apps/web/src/arcade-games/math-sprint/game.yaml

@@ -0,0 +1,16 @@
+name: math-sprint
+displayName: Math Sprint
+icon: 🧮
+description: Fast-paced math racing game
+longDescription: Race against other players to solve math problems! Answer questions quickly to earn points. First person to answer correctly wins the round. Features multiple difficulty levels and customizable question counts.
+maxPlayers: 6
+difficulty: Beginner
+chips:
+  - 👥 Multiplayer
+  - ⚡ Free-for-All
+  - 🧮 Math Skills
+  - 🏃 Speed
+color: purple
+gradient: linear-gradient(135deg, #ddd6fe, #c4b5fd)
+borderColor: purple.200
+available: true

apps/web/src/arcade-games/math-sprint/index.ts

@@ -0,0 +1,43 @@
+/**
+ * Math Sprint Game Definition
+ *
+ * A free-for-all math game demonstrating the TEAM_MOVE pattern.
+ * Players race to solve math problems - first correct answer wins points.
+ */
+
+import { defineGame } from '@/lib/arcade/game-sdk'
+import type { GameManifest } from '@/lib/arcade/game-sdk'
+import { GameComponent } from './components/GameComponent'
+import { MathSprintProvider } from './Provider'
+import type { MathSprintConfig, MathSprintMove, MathSprintState } from './types'
+import { mathSprintValidator } from './Validator'
+
+const manifest: GameManifest = {
+  name: 'math-sprint',
+  displayName: 'Math Sprint',
+  icon: '🧮',
+  description: 'Race to solve math problems!',
+  longDescription:
+    'A fast-paced free-for-all game where players compete to solve math problems. First correct answer earns points. Choose your difficulty and test your mental math skills!',
+  maxPlayers: 8,
+  difficulty: 'Beginner',
+  chips: ['👥 Multiplayer', '⚡ Fast-Paced', '🧠 Mental Math'],
+  color: 'purple',
+  gradient: 'linear-gradient(135deg, #ddd6fe, #c4b5fd)',
+  borderColor: 'purple.200',
+  available: true,
+}
+
+const defaultConfig: MathSprintConfig = {
+  difficulty: 'medium',
+  questionsPerRound: 10,
+  timePerQuestion: 30,
+}
+
+export const mathSprintGame = defineGame<MathSprintConfig, MathSprintState, MathSprintMove>({
+  manifest,
+  Provider: MathSprintProvider,
+  GameComponent,
+  validator: mathSprintValidator,
+  defaultConfig,
+})

apps/web/src/arcade-games/math-sprint/types.ts

@@ -0,0 +1,120 @@
+/**
+ * Math Sprint Game Types
+ *
+ * A free-for-all game where players race to solve math problems.
+ * Demonstrates the TEAM_MOVE pattern (no specific turn owner).
+ */
+
+import type { GameConfig, GameMove, GameState } from '@/lib/arcade/game-sdk'
+
+/**
+ * Difficulty levels for math problems
+ */
+export type Difficulty = 'easy' | 'medium' | 'hard'
+
+/**
+ * Math operation types
+ */
+export type Operation = 'addition' | 'subtraction' | 'multiplication'
+
+/**
+ * Game configuration (persisted to database)
+ */
+export interface MathSprintConfig extends GameConfig {
+  difficulty: Difficulty
+  questionsPerRound: number
+  timePerQuestion: number // seconds
+}
+
+/**
+ * A math question
+ */
+export interface Question {
+  id: string
+  operand1: number
+  operand2: number
+  operation: Operation
+  correctAnswer: number
+  displayText: string // e.g., "5 + 3 = ?"
+}
+
+/**
+ * Player answer submission
+ */
+export interface Answer {
+  playerId: string
+  answer: number
+  timestamp: number
+  correct: boolean
+}
+
+/**
+ * Game state (synchronized across all clients)
+ */
+export interface MathSprintState extends GameState {
+  gamePhase: 'setup' | 'playing' | 'results'
+  activePlayers: string[]
+  playerMetadata: Record<string, { name: string; emoji: string; color: string; userId: string }>
+
+  // Configuration
+  difficulty: Difficulty
+  questionsPerRound: number
+  timePerQuestion: number
+
+  // Game progress
+  currentQuestionIndex: number
+  questions: Question[]
+
+  // Scoring
+  scores: Record<string, number> // playerId -> score
+  correctAnswersCount: Record<string, number> // playerId -> count
+
+  // Current question state
+  answers: Answer[] // All answers for current question
+  questionStartTime: number // Timestamp when question was shown
+  questionAnswered: boolean // True if someone got it right
+  winnerId: string | null // Winner of current question (first correct)
+}
+
+/**
+ * Move types for Math Sprint
+ */
+export type MathSprintMove =
+  | StartGameMove
+  | SubmitAnswerMove
+  | NextQuestionMove
+  | ResetGameMove
+  | SetConfigMove
+
+export interface StartGameMove extends GameMove {
+  type: 'START_GAME'
+  data: {
+    activePlayers: string[]
+    playerMetadata: Record<string, unknown>
+  }
+}
+
+export interface SubmitAnswerMove extends GameMove {
+  type: 'SUBMIT_ANSWER'
+  data: {
+    answer: number
+  }
+}
+
+export interface NextQuestionMove extends GameMove {
+  type: 'NEXT_QUESTION'
+  data: Record<string, never>
+}
+
+export interface ResetGameMove extends GameMove {
+  type: 'RESET_GAME'
+  data: Record<string, never>
+}
+
+export interface SetConfigMove extends GameMove {
+  type: 'SET_CONFIG'
+  data: {
+    field: 'difficulty' | 'questionsPerRound' | 'timePerQuestion'
+    value: Difficulty | number
+  }
+}

apps/web/src/arcade-games/number-guesser/Provider.tsx

@@ -0,0 +1,215 @@
+/**
+ * Number Guesser Provider
+ * Manages game state using the Arcade SDK
+ */
+
+'use client'
+
+import { createContext, useCallback, useContext, useMemo, type ReactNode } from 'react'
+import {
+  type GameMove,
+  buildPlayerMetadata,
+  useArcadeSession,
+  useGameMode,
+  useRoomData,
+  useUpdateGameConfig,
+  useViewerId,
+} from '@/lib/arcade/game-sdk'
+import type { NumberGuesserState } from './types'
+
+/**
+ * Context value interface
+ */
+interface NumberGuesserContextValue {
+  state: NumberGuesserState
+  lastError: string | null
+  startGame: () => void
+  chooseNumber: (number: number) => void
+  makeGuess: (guess: number) => void
+  nextRound: () => void
+  goToSetup: () => void
+  setConfig: (field: 'minNumber' | 'maxNumber' | 'roundsToWin', value: number) => void
+  clearError: () => void
+  exitSession: () => void
+}
+
+const NumberGuesserContext = createContext<NumberGuesserContextValue | null>(null)
+
+/**
+ * Hook to access Number Guesser context
+ */
+export function useNumberGuesser() {
+  const context = useContext(NumberGuesserContext)
+  if (!context) {
+    throw new Error('useNumberGuesser must be used within NumberGuesserProvider')
+  }
+  return context
+}
+
+/**
+ * Optimistic move application
+ */
+function applyMoveOptimistically(state: NumberGuesserState, move: GameMove): NumberGuesserState {
+  // For simplicity, just return current state
+  // Server will send back the validated new state
+  return state
+}
+
+/**
+ * Number Guesser Provider Component
+ */
+export function NumberGuesserProvider({ children }: { children: ReactNode }) {
+  const { data: viewerId } = useViewerId()
+  const { roomData } = useRoomData()
+  const { activePlayers: activePlayerIds, players } = useGameMode()
+  const { mutate: updateGameConfig } = useUpdateGameConfig()
+
+  // Get active players as array (keep Set iteration order to match UI display)
+  const activePlayers = Array.from(activePlayerIds)
+
+  // Merge saved config from room
+  const initialState = useMemo(() => {
+    const gameConfig = roomData?.gameConfig as Record<string, unknown> | null | undefined
+    const savedConfig = gameConfig?.['number-guesser'] as Record<string, unknown> | undefined
+
+    return {
+      minNumber: (savedConfig?.minNumber as number) || 1,
+      maxNumber: (savedConfig?.maxNumber as number) || 100,
+      roundsToWin: (savedConfig?.roundsToWin as number) || 3,
+      gamePhase: 'setup' as const,
+      activePlayers: [],
+      playerMetadata: {},
+      secretNumber: null,
+      chooser: '',
+      currentGuesser: '',
+      guesses: [],
+      roundNumber: 0,
+      scores: {},
+      gameStartTime: null,
+      gameEndTime: null,
+      winner: null,
+    }
+  }, [roomData?.gameConfig])
+
+  // Arcade session integration
+  const { state, sendMove, exitSession, lastError, clearError } =
+    useArcadeSession<NumberGuesserState>({
+      userId: viewerId || '',
+      roomId: roomData?.id,
+      initialState,
+      applyMove: applyMoveOptimistically,
+    })
+
+  // Action creators
+  const startGame = useCallback(() => {
+    if (activePlayers.length < 2) {
+      console.error('Need at least 2 players to start')
+      return
+    }
+
+    const playerMetadata = buildPlayerMetadata(activePlayers, {}, players, viewerId || undefined)
+
+    sendMove({
+      type: 'START_GAME',
+      playerId: activePlayers[0],
+      userId: viewerId || '',
+      data: {
+        activePlayers,
+        playerMetadata,
+      },
+    })
+  }, [activePlayers, players, viewerId, sendMove])
+
+  const chooseNumber = useCallback(
+    (secretNumber: number) => {
+      sendMove({
+        type: 'CHOOSE_NUMBER',
+        playerId: state.chooser,
+        userId: viewerId || '',
+        data: { secretNumber },
+      })
+    },
+    [state.chooser, viewerId, sendMove]
+  )
+
+  const makeGuess = useCallback(
+    (guess: number) => {
+      const playerName = state.playerMetadata[state.currentGuesser]?.name || 'Unknown'
+
+      sendMove({
+        type: 'MAKE_GUESS',
+        playerId: state.currentGuesser,
+        userId: viewerId || '',
+        data: { guess, playerName },
+      })
+    },
+    [state.currentGuesser, state.playerMetadata, viewerId, sendMove]
+  )
+
+  const nextRound = useCallback(() => {
+    sendMove({
+      type: 'NEXT_ROUND',
+      playerId: activePlayers[0] || '',
+      userId: viewerId || '',
+      data: {},
+    })
+  }, [activePlayers, viewerId, sendMove])
+
+  const goToSetup = useCallback(() => {
+    sendMove({
+      type: 'GO_TO_SETUP',
+      playerId: activePlayers[0] || state.chooser || '',
+      userId: viewerId || '',
+      data: {},
+    })
+  }, [activePlayers, state.chooser, viewerId, sendMove])
+
+  const setConfig = useCallback(
+    (field: 'minNumber' | 'maxNumber' | 'roundsToWin', value: number) => {
+      sendMove({
+        type: 'SET_CONFIG',
+        playerId: activePlayers[0] || '',
+        userId: viewerId || '',
+        data: { field, value },
+      })
+
+      // Persist to database
+      if (roomData?.id) {
+        const currentGameConfig = (roomData.gameConfig as Record<string, unknown>) || {}
+        const currentNumberGuesserConfig =
+          (currentGameConfig['number-guesser'] as Record<string, unknown>) || {}
+
+        const updatedConfig = {
+          ...currentGameConfig,
+          'number-guesser': {
+            ...currentNumberGuesserConfig,
+            [field]: value,
+          },
+        }
+
+        updateGameConfig({
+          roomId: roomData.id,
+          gameConfig: updatedConfig,
+        })
+      }
+    },
+    [activePlayers, viewerId, sendMove, roomData?.id, roomData?.gameConfig, updateGameConfig]
+  )
+
+  const contextValue: NumberGuesserContextValue = {
+    state,
+    lastError,
+    startGame,
+    chooseNumber,
+    makeGuess,
+    nextRound,
+    goToSetup,
+    setConfig,
+    clearError,
+    exitSession,
+  }
+
+  return (
+    <NumberGuesserContext.Provider value={contextValue}>{children}</NumberGuesserContext.Provider>
+  )
+}

apps/web/src/arcade-games/number-guesser/Validator.ts

@@ -0,0 +1,315 @@
+/**
+ * Server-side validator for Number Guesser game
+ */
+
+import type { GameValidator, ValidationResult } from '@/lib/arcade/game-sdk'
+import type { NumberGuesserConfig, NumberGuesserMove, NumberGuesserState } from './types'
+
+export class NumberGuesserValidator
+  implements GameValidator<NumberGuesserState, NumberGuesserMove>
+{
+  validateMove(state: NumberGuesserState, move: NumberGuesserMove): ValidationResult {
+    switch (move.type) {
+      case 'START_GAME':
+        return this.validateStartGame(state, move.data.activePlayers, move.data.playerMetadata)
+
+      case 'CHOOSE_NUMBER':
+        // Ensure secretNumber is a number (JSON deserialization can make it a string)
+        return this.validateChooseNumber(state, Number(move.data.secretNumber), move.playerId)
+
+      case 'MAKE_GUESS':
+        // Ensure guess is a number (JSON deserialization can make it a string)
+        return this.validateMakeGuess(
+          state,
+          Number(move.data.guess),
+          move.playerId,
+          move.data.playerName
+        )
+
+      case 'NEXT_ROUND':
+        return this.validateNextRound(state)
+
+      case 'GO_TO_SETUP':
+        return this.validateGoToSetup(state)
+
+      case 'SET_CONFIG':
+        // Ensure value is a number (JSON deserialization can make it a string)
+        return this.validateSetConfig(state, move.data.field, Number(move.data.value))
+
+      default:
+        return {
+          valid: false,
+          error: `Unknown move type: ${(move as { type: string }).type}`,
+        }
+    }
+  }
+
+  private validateStartGame(
+    state: NumberGuesserState,
+    activePlayers: string[],
+    playerMetadata: Record<string, unknown>
+  ): ValidationResult {
+    if (!activePlayers || activePlayers.length < 2) {
+      return { valid: false, error: 'Need at least 2 players' }
+    }
+
+    const newState: NumberGuesserState = {
+      ...state,
+      gamePhase: 'choosing',
+      activePlayers,
+      playerMetadata: playerMetadata as typeof state.playerMetadata,
+      chooser: activePlayers[0],
+      currentGuesser: '',
+      secretNumber: null,
+      guesses: [],
+      roundNumber: 1,
+      scores: activePlayers.reduce((acc, p) => ({ ...acc, [p]: 0 }), {}),
+      gameStartTime: Date.now(),
+      gameEndTime: null,
+      winner: null,
+    }
+
+    return { valid: true, newState }
+  }
+
+  private validateChooseNumber(
+    state: NumberGuesserState,
+    secretNumber: number,
+    playerId: string
+  ): ValidationResult {
+    if (state.gamePhase !== 'choosing') {
+      return { valid: false, error: 'Not in choosing phase' }
+    }
+
+    if (playerId !== state.chooser) {
+      return { valid: false, error: 'Not your turn to choose' }
+    }
+
+    if (
+      secretNumber < state.minNumber ||
+      secretNumber > state.maxNumber ||
+      !Number.isInteger(secretNumber)
+    ) {
+      return {
+        valid: false,
+        error: `Number must be between ${state.minNumber} and ${state.maxNumber}`,
+      }
+    }
+
+    // Debug logging
+    console.log('[NumberGuesser] Setting secret number:', {
+      secretNumber,
+      secretNumberType: typeof secretNumber,
+    })
+
+    // First guesser is the next player after chooser
+    const chooserIndex = state.activePlayers.indexOf(state.chooser)
+    const firstGuesserIndex = (chooserIndex + 1) % state.activePlayers.length
+    const firstGuesser = state.activePlayers[firstGuesserIndex]
+
+    const newState: NumberGuesserState = {
+      ...state,
+      gamePhase: 'guessing',
+      secretNumber,
+      currentGuesser: firstGuesser,
+    }
+
+    return { valid: true, newState }
+  }
+
+  private validateMakeGuess(
+    state: NumberGuesserState,
+    guess: number,
+    playerId: string,
+    playerName: string
+  ): ValidationResult {
+    if (state.gamePhase !== 'guessing') {
+      return { valid: false, error: 'Not in guessing phase' }
+    }
+
+    if (playerId !== state.currentGuesser) {
+      return { valid: false, error: 'Not your turn to guess' }
+    }
+
+    if (guess < state.minNumber || guess > state.maxNumber || !Number.isInteger(guess)) {
+      return {
+        valid: false,
+        error: `Guess must be between ${state.minNumber} and ${state.maxNumber}`,
+      }
+    }
+
+    if (!state.secretNumber) {
+      return { valid: false, error: 'No secret number set' }
+    }
+
+    // Debug logging
+    console.log('[NumberGuesser] Validating guess:', {
+      guess,
+      guessType: typeof guess,
+      secretNumber: state.secretNumber,
+      secretNumberType: typeof state.secretNumber,
+    })
+
+    const distance = Math.abs(guess - state.secretNumber)
+
+    console.log('[NumberGuesser] Calculated distance:', distance)
+    const newGuess = {
+      playerId,
+      playerName,
+      guess,
+      distance,
+      timestamp: Date.now(),
+    }
+
+    const guesses = [...state.guesses, newGuess]
+
+    // Check if guess is correct
+    if (distance === 0) {
+      // Correct guess! Award point and end round
+      const newScores = {
+        ...state.scores,
+        [playerId]: (state.scores[playerId] || 0) + 1,
+      }
+
+      // Check if player won
+      const winner = newScores[playerId] >= state.roundsToWin ? playerId : null
+
+      const newState: NumberGuesserState = {
+        ...state,
+        guesses,
+        scores: newScores,
+        gamePhase: winner ? 'results' : 'guessing',
+        gameEndTime: winner ? Date.now() : null,
+        winner,
+      }
+
+      return { valid: true, newState }
+    }
+
+    // Incorrect guess, move to next guesser
+    const guesserIndex = state.activePlayers.indexOf(state.currentGuesser)
+    let nextGuesserIndex = (guesserIndex + 1) % state.activePlayers.length
+
+    // Skip the chooser
+    if (state.activePlayers[nextGuesserIndex] === state.chooser) {
+      nextGuesserIndex = (nextGuesserIndex + 1) % state.activePlayers.length
+    }
+
+    const newState: NumberGuesserState = {
+      ...state,
+      guesses,
+      currentGuesser: state.activePlayers[nextGuesserIndex],
+    }
+
+    return { valid: true, newState }
+  }
+
+  private validateNextRound(state: NumberGuesserState): ValidationResult {
+    if (state.gamePhase !== 'guessing') {
+      return { valid: false, error: 'Not in guessing phase' }
+    }
+
+    // Check if the round is complete (someone guessed correctly)
+    const roundComplete =
+      state.guesses.length > 0 && state.guesses[state.guesses.length - 1].distance === 0
+
+    if (!roundComplete) {
+      return { valid: false, error: 'Round not complete yet - no one has guessed the number' }
+    }
+
+    // Rotate chooser to next player
+    const chooserIndex = state.activePlayers.indexOf(state.chooser)
+    const nextChooserIndex = (chooserIndex + 1) % state.activePlayers.length
+    const nextChooser = state.activePlayers[nextChooserIndex]
+
+    const newState: NumberGuesserState = {
+      ...state,
+      gamePhase: 'choosing',
+      chooser: nextChooser,
+      currentGuesser: '',
+      secretNumber: null,
+      guesses: [],
+      roundNumber: state.roundNumber + 1,
+      winner: null,
+    }
+
+    return { valid: true, newState }
+  }
+
+  private validateGoToSetup(state: NumberGuesserState): ValidationResult {
+    const newState: NumberGuesserState = {
+      ...state,
+      gamePhase: 'setup',
+      secretNumber: null,
+      chooser: '',
+      currentGuesser: '',
+      guesses: [],
+      roundNumber: 0,
+      scores: {},
+      activePlayers: [],
+      playerMetadata: {},
+      gameStartTime: null,
+      gameEndTime: null,
+      winner: null,
+    }
+
+    return { valid: true, newState }
+  }
+
+  private validateSetConfig(
+    state: NumberGuesserState,
+    field: 'minNumber' | 'maxNumber' | 'roundsToWin',
+    value: number
+  ): ValidationResult {
+    if (state.gamePhase !== 'setup') {
+      return { valid: false, error: 'Can only change config in setup' }
+    }
+
+    if (!Number.isInteger(value) || value < 1) {
+      return { valid: false, error: 'Value must be a positive integer' }
+    }
+
+    if (field === 'minNumber' && value >= state.maxNumber) {
+      return { valid: false, error: 'Min must be less than max' }
+    }
+
+    if (field === 'maxNumber' && value <= state.minNumber) {
+      return { valid: false, error: 'Max must be greater than min' }
+    }
+
+    const newState: NumberGuesserState = {
+      ...state,
+      [field]: value,
+    }
+
+    return { valid: true, newState }
+  }
+
+  isGameComplete(state: NumberGuesserState): boolean {
+    return state.gamePhase === 'results' && state.winner !== null
+  }
+
+  getInitialState(config: unknown): NumberGuesserState {
+    const { minNumber, maxNumber, roundsToWin } = config as NumberGuesserConfig
+
+    return {
+      minNumber: minNumber || 1,
+      maxNumber: maxNumber || 100,
+      roundsToWin: roundsToWin || 3,
+      gamePhase: 'setup',
+      activePlayers: [],
+      playerMetadata: {},
+      secretNumber: null,
+      chooser: '',
+      currentGuesser: '',
+      guesses: [],
+      roundNumber: 0,
+      scores: {},
+      gameStartTime: null,
+      gameEndTime: null,
+      winner: null,
+    }
+  }
+}
+
+export const numberGuesserValidator = new NumberGuesserValidator()

apps/web/src/arcade-games/number-guesser/components/ChoosingPhase.tsx

@@ -0,0 +1,211 @@
+/**
+ * Choosing Phase - Chooser picks a secret number
+ */
+
+'use client'
+
+import { useState } from 'react'
+import { useViewerId } from '@/lib/arcade/game-sdk'
+import { css } from '../../../../styled-system/css'
+import { useNumberGuesser } from '../Provider'
+
+export function ChoosingPhase() {
+  const { state, chooseNumber } = useNumberGuesser()
+  const { data: viewerId } = useViewerId()
+  const [inputValue, setInputValue] = useState('')
+
+  const chooserMetadata = state.playerMetadata[state.chooser]
+  const isChooser = chooserMetadata?.userId === viewerId
+
+  const handleSubmit = () => {
+    const number = Number.parseInt(inputValue, 10)
+    if (Number.isNaN(number)) return
+
+    chooseNumber(number)
+  }
+
+  return (
+    <div
+      className={css({
+        padding: '32px',
+        maxWidth: '600px',
+        margin: '0 auto',
+      })}
+    >
+      <div
+        className={css({
+          textAlign: 'center',
+          marginBottom: '32px',
+        })}
+      >
+        <div
+          className={css({
+            fontSize: '64px',
+            marginBottom: '16px',
+          })}
+        >
+          {chooserMetadata?.emoji || '🤔'}
+        </div>
+        <h2
+          className={css({
+            fontSize: '2xl',
+            fontWeight: 'bold',
+            marginBottom: '8px',
+          })}
+        >
+          {isChooser ? "You're choosing!" : `${chooserMetadata?.name || 'Someone'} is choosing...`}
+        </h2>
+        <p
+          className={css({
+            color: 'gray.600',
+          })}
+        >
+          Round {state.roundNumber}
+        </p>
+      </div>
+
+      {isChooser ? (
+        <div
+          className={css({
+            background: 'white',
+            border: '2px solid',
+            borderColor: 'orange.200',
+            borderRadius: '12px',
+            padding: '24px',
+          })}
+        >
+          <label
+            className={css({
+              display: 'block',
+              fontSize: 'md',
+              fontWeight: '600',
+              marginBottom: '12px',
+              textAlign: 'center',
+            })}
+          >
+            Choose a secret number ({state.minNumber} - {state.maxNumber})
+          </label>
+          <input
+            type="number"
+            value={inputValue}
+            onChange={(e) => setInputValue(e.target.value)}
+            min={state.minNumber}
+            max={state.maxNumber}
+            placeholder={`${state.minNumber} - ${state.maxNumber}`}
+            className={css({
+              width: '100%',
+              padding: '16px',
+              border: '2px solid',
+              borderColor: 'gray.300',
+              borderRadius: '8px',
+              fontSize: 'xl',
+              textAlign: 'center',
+              marginBottom: '16px',
+            })}
+          />
+          <button
+            onClick={handleSubmit}
+            disabled={!inputValue}
+            className={css({
+              width: '100%',
+              padding: '16px',
+              background: 'linear-gradient(135deg, #fb923c, #f97316)',
+              color: 'white',
+              border: 'none',
+              borderRadius: '8px',
+              fontSize: 'lg',
+              fontWeight: 'bold',
+              cursor: 'pointer',
+              transition: 'all 0.2s',
+              _disabled: {
+                opacity: 0.5,
+                cursor: 'not-allowed',
+              },
+              _hover: {
+                transform: 'translateY(-2px)',
+              },
+            })}
+          >
+            Confirm Choice
+          </button>
+        </div>
+      ) : (
+        <div
+          className={css({
+            background: 'white',
+            border: '2px solid',
+            borderColor: 'orange.200',
+            borderRadius: '12px',
+            padding: '32px',
+            textAlign: 'center',
+          })}
+        >
+          <div
+            className={css({
+              fontSize: '48px',
+              marginBottom: '16px',
+            })}
+          >
+            ⏳
+          </div>
+          <p
+            className={css({
+              fontSize: 'lg',
+              color: 'gray.600',
+            })}
+          >
+            Waiting for {chooserMetadata?.name || 'player'} to choose a number...
+          </p>
+        </div>
+      )}
+
+      {/* Scoreboard */}
+      <div
+        className={css({
+          marginTop: '32px',
+          background: 'white',
+          border: '1px solid',
+          borderColor: 'gray.200',
+          borderRadius: '12px',
+          padding: '16px',
+        })}
+      >
+        <h3
+          className={css({
+            fontSize: 'md',
+            fontWeight: 'bold',
+            marginBottom: '12px',
+            textAlign: 'center',
+          })}
+        >
+          Scores
+        </h3>
+        <div
+          className={css({
+            display: 'flex',
+            flexWrap: 'wrap',
+            gap: '8px',
+            justifyContent: 'center',
+          })}
+        >
+          {state.activePlayers.map((playerId) => {
+            const player = state.playerMetadata[playerId]
+            return (
+              <div
+                key={playerId}
+                className={css({
+                  padding: '8px 16px',
+                  background: 'gray.100',
+                  borderRadius: '8px',
+                  fontSize: 'sm',
+                })}
+              >
+                {player?.emoji} {player?.name}: {state.scores[playerId] || 0}
+              </div>
+            )
+          })}
+        </div>
+      </div>
+    </div>
+  )
+}

apps/web/src/arcade-games/number-guesser/components/GameComponent.tsx

@@ -0,0 +1,60 @@
+/**
+ * Number Guesser Game Component
+ * Main component that switches between game phases
+ */
+
+'use client'
+
+import { useRouter } from 'next/navigation'
+import { PageWithNav } from '@/components/PageWithNav'
+import { useNumberGuesser } from '../Provider'
+import { ChoosingPhase } from './ChoosingPhase'
+import { GuessingPhase } from './GuessingPhase'
+import { ResultsPhase } from './ResultsPhase'
+import { SetupPhase } from './SetupPhase'
+
+export function GameComponent() {
+  const router = useRouter()
+  const { state, exitSession, goToSetup } = useNumberGuesser()
+
+  // Determine whose turn it is based on game phase
+  const currentPlayerId =
+    state.gamePhase === 'choosing'
+      ? state.chooser
+      : state.gamePhase === 'guessing'
+        ? state.currentGuesser
+        : undefined
+
+  return (
+    <PageWithNav
+      navTitle="Number Guesser"
+      navEmoji="🎯"
+      emphasizePlayerSelection={state.gamePhase === 'setup'}
+      currentPlayerId={currentPlayerId}
+      playerScores={state.scores}
+      onExitSession={() => {
+        exitSession?.()
+        router.push('/arcade')
+      }}
+      onNewGame={() => {
+        goToSetup?.()
+      }}
+    >
+      <div
+        style={{
+          flex: 1,
+          display: 'flex',
+          flexDirection: 'column',
+          overflow: 'auto',
+          minHeight: '100vh',
+          background: 'linear-gradient(135deg, #fff7ed, #ffedd5)',
+        }}
+      >
+        {state.gamePhase === 'setup' && <SetupPhase />}
+        {state.gamePhase === 'choosing' && <ChoosingPhase />}
+        {state.gamePhase === 'guessing' && <GuessingPhase />}
+        {state.gamePhase === 'results' && <ResultsPhase />}
+      </div>
+    </PageWithNav>
+  )
+}

apps/web/src/arcade-games/number-guesser/components/GuessingPhase.tsx

@@ -0,0 +1,445 @@
+/**
+ * Guessing Phase - Players take turns guessing the secret number
+ */
+
+'use client'
+
+import { useEffect, useState } from 'react'
+import { useViewerId } from '@/lib/arcade/game-sdk'
+import { css } from '../../../../styled-system/css'
+import { useNumberGuesser } from '../Provider'
+
+export function GuessingPhase() {
+  const { state, makeGuess, nextRound, lastError, clearError } = useNumberGuesser()
+  const { data: viewerId } = useViewerId()
+  const [inputValue, setInputValue] = useState('')
+
+  const currentGuesserMetadata = state.playerMetadata[state.currentGuesser]
+  const isCurrentGuesser = currentGuesserMetadata?.userId === viewerId
+
+  // Check if someone just won the round
+  const lastGuess = state.guesses[state.guesses.length - 1]
+  const roundJustEnded = lastGuess?.distance === 0
+
+  // Auto-clear error after 5 seconds
+  useEffect(() => {
+    if (lastError) {
+      const timeout = setTimeout(() => clearError(), 5000)
+      return () => clearTimeout(timeout)
+    }
+  }, [lastError, clearError])
+
+  const handleSubmit = () => {
+    const guess = Number.parseInt(inputValue, 10)
+    if (Number.isNaN(guess)) return
+
+    makeGuess(guess)
+    setInputValue('')
+  }
+
+  const getHotColdMessage = (distance: number) => {
+    if (distance === 0) return '🎯 Correct!'
+    if (distance <= 5) return '🔥 Very Hot!'
+    if (distance <= 10) return '🌡️ Hot'
+    if (distance <= 20) return '😊 Warm'
+    if (distance <= 30) return '😐 Cool'
+    if (distance <= 50) return '❄️ Cold'
+    return '🧊 Very Cold'
+  }
+
+  return (
+    <div
+      className={css({
+        padding: '32px',
+        maxWidth: '800px',
+        margin: '0 auto',
+      })}
+    >
+      {/* Header */}
+      <div
+        className={css({
+          textAlign: 'center',
+          marginBottom: '32px',
+        })}
+      >
+        <div
+          className={css({
+            fontSize: '64px',
+            marginBottom: '16px',
+          })}
+        >
+          {roundJustEnded ? '🎉' : currentGuesserMetadata?.emoji || '🤔'}
+        </div>
+        <h2
+          className={css({
+            fontSize: '2xl',
+            fontWeight: 'bold',
+            marginBottom: '8px',
+          })}
+        >
+          {roundJustEnded
+            ? `${lastGuess.playerName} guessed it!`
+            : isCurrentGuesser
+              ? 'Your turn to guess!'
+              : `${currentGuesserMetadata?.name || 'Someone'} is guessing...`}
+        </h2>
+        <p
+          className={css({
+            color: 'gray.600',
+          })}
+        >
+          Round {state.roundNumber} • Range: {state.minNumber} - {state.maxNumber}
+        </p>
+      </div>
+
+      {/* Error Banner */}
+      {lastError && (
+        <div
+          className={css({
+            background: 'linear-gradient(135deg, #fef2f2, #fee2e2)',
+            border: '2px solid',
+            borderColor: 'red.300',
+            borderRadius: '12px',
+            padding: '16px 20px',
+            marginBottom: '24px',
+            display: 'flex',
+            alignItems: 'center',
+            justifyContent: 'space-between',
+            animation: 'slideIn 0.3s ease',
+          })}
+        >
+          <div
+            className={css({
+              display: 'flex',
+              alignItems: 'center',
+              gap: '12px',
+            })}
+          >
+            <div
+              className={css({
+                fontSize: '24px',
+              })}
+            >
+              ⚠️
+            </div>
+            <div>
+              <div
+                className={css({
+                  fontSize: 'md',
+                  fontWeight: 'bold',
+                  color: 'red.700',
+                  marginBottom: '4px',
+                })}
+              >
+                Move Rejected
+              </div>
+              <div
+                className={css({
+                  fontSize: 'sm',
+                  color: 'red.600',
+                })}
+              >
+                {lastError}
+              </div>
+            </div>
+          </div>
+          <button
+            type="button"
+            onClick={clearError}
+            className={css({
+              padding: '8px 12px',
+              background: 'white',
+              border: '1px solid',
+              borderColor: 'red.300',
+              borderRadius: '6px',
+              fontSize: 'sm',
+              fontWeight: '600',
+              color: 'red.700',
+              cursor: 'pointer',
+              transition: 'all 0.2s',
+              _hover: {
+                background: 'red.50',
+              },
+            })}
+          >
+            Dismiss
+          </button>
+        </div>
+      )}
+
+      {/* Round ended - show next round button */}
+      {roundJustEnded && (
+        <div
+          className={css({
+            background: 'white',
+            border: '2px solid',
+            borderColor: 'green.200',
+            borderRadius: '12px',
+            padding: '24px',
+            marginBottom: '24px',
+            textAlign: 'center',
+          })}
+        >
+          <div
+            className={css({
+              fontSize: '48px',
+              marginBottom: '16px',
+            })}
+          >
+            🎯
+          </div>
+          <p
+            className={css({
+              fontSize: 'lg',
+              marginBottom: '16px',
+            })}
+          >
+            The secret number was <strong>{state.secretNumber}</strong>!
+          </p>
+          <button
+            type="button"
+            onClick={nextRound}
+            className={css({
+              padding: '12px 24px',
+              background: 'linear-gradient(135deg, #fb923c, #f97316)',
+              color: 'white',
+              border: 'none',
+              borderRadius: '8px',
+              fontSize: 'md',
+              fontWeight: 'bold',
+              cursor: 'pointer',
+              transition: 'all 0.2s',
+              _hover: {
+                transform: 'translateY(-2px)',
+              },
+            })}
+          >
+            Next Round
+          </button>
+        </div>
+      )}
+
+      {/* Guessing input (only if round not ended) */}
+      {!roundJustEnded && (
+        <div
+          className={css({
+            background: 'white',
+            border: '2px solid',
+            borderColor: 'orange.200',
+            borderRadius: '12px',
+            padding: '24px',
+            marginBottom: '24px',
+          })}
+        >
+          {isCurrentGuesser ? (
+            <>
+              <label
+                className={css({
+                  display: 'block',
+                  fontSize: 'md',
+                  fontWeight: '600',
+                  marginBottom: '12px',
+                  textAlign: 'center',
+                })}
+              >
+                Make your guess ({state.minNumber} - {state.maxNumber})
+              </label>
+              <input
+                type="number"
+                value={inputValue}
+                onChange={(e) => setInputValue(e.target.value)}
+                onKeyDown={(e) => {
+                  if (e.key === 'Enter' && inputValue) {
+                    handleSubmit()
+                  }
+                }}
+                min={state.minNumber}
+                max={state.maxNumber}
+                placeholder={`${state.minNumber} - ${state.maxNumber}`}
+                className={css({
+                  width: '100%',
+                  padding: '16px',
+                  border: '2px solid',
+                  borderColor: 'gray.300',
+                  borderRadius: '8px',
+                  fontSize: 'xl',
+                  textAlign: 'center',
+                  marginBottom: '16px',
+                })}
+              />
+              <button
+                type="button"
+                onClick={handleSubmit}
+                disabled={!inputValue}
+                className={css({
+                  width: '100%',
+                  padding: '16px',
+                  background: 'linear-gradient(135deg, #fb923c, #f97316)',
+                  color: 'white',
+                  border: 'none',
+                  borderRadius: '8px',
+                  fontSize: 'lg',
+                  fontWeight: 'bold',
+                  cursor: 'pointer',
+                  transition: 'all 0.2s',
+                  _disabled: {
+                    opacity: 0.5,
+                    cursor: 'not-allowed',
+                  },
+                  _hover: {
+                    transform: 'translateY(-2px)',
+                  },
+                })}
+              >
+                Submit Guess
+              </button>
+            </>
+          ) : (
+            <div
+              className={css({
+                textAlign: 'center',
+                padding: '16px',
+              })}
+            >
+              <div
+                className={css({
+                  fontSize: '48px',
+                  marginBottom: '16px',
+                })}
+              >
+                ⏳
+              </div>
+              <p
+                className={css({
+                  fontSize: 'lg',
+                  color: 'gray.600',
+                })}
+              >
+                Waiting for {currentGuesserMetadata?.name || 'player'} to guess...
+              </p>
+            </div>
+          )}
+        </div>
+      )}
+
+      {/* Guess history */}
+      {state.guesses.length > 0 && (
+        <div
+          className={css({
+            background: 'white',
+            border: '1px solid',
+            borderColor: 'gray.200',
+            borderRadius: '12px',
+            padding: '16px',
+            marginBottom: '24px',
+          })}
+        >
+          <h3
+            className={css({
+              fontSize: 'md',
+              fontWeight: 'bold',
+              marginBottom: '12px',
+            })}
+          >
+            Guess History
+          </h3>
+          <div
+            className={css({
+              display: 'flex',
+              flexDirection: 'column',
+              gap: '8px',
+            })}
+          >
+            {state.guesses.map((guess, index) => {
+              const player = state.playerMetadata[guess.playerId]
+              return (
+                <div
+                  key={index}
+                  className={css({
+                    padding: '12px',
+                    background: guess.distance === 0 ? 'green.50' : 'gray.50',
+                    borderRadius: '8px',
+                    display: 'flex',
+                    justifyContent: 'space-between',
+                    alignItems: 'center',
+                  })}
+                >
+                  <div
+                    className={css({
+                      display: 'flex',
+                      alignItems: 'center',
+                      gap: '8px',
+                    })}
+                  >
+                    <span>{player?.emoji || '🎮'}</span>
+                    <span className={css({ fontWeight: '600' })}>{guess.playerName}</span>
+                    <span className={css({ color: 'gray.600' })}>guessed</span>
+                    <span className={css({ fontWeight: 'bold', fontSize: 'lg' })}>
+                      {guess.guess}
+                    </span>
+                  </div>
+                  <div
+                    className={css({
+                      fontWeight: 'bold',
+                      color: guess.distance === 0 ? 'green.700' : 'orange.700',
+                    })}
+                  >
+                    {getHotColdMessage(guess.distance)}
+                  </div>
+                </div>
+              )
+            })}
+          </div>
+        </div>
+      )}
+
+      {/* Scoreboard */}
+      <div
+        className={css({
+          background: 'white',
+          border: '1px solid',
+          borderColor: 'gray.200',
+          borderRadius: '12px',
+          padding: '16px',
+        })}
+      >
+        <h3
+          className={css({
+            fontSize: 'md',
+            fontWeight: 'bold',
+            marginBottom: '12px',
+            textAlign: 'center',
+          })}
+        >
+          Scores (First to {state.roundsToWin} wins!)
+        </h3>
+        <div
+          className={css({
+            display: 'flex',
+            flexWrap: 'wrap',
+            gap: '8px',
+            justifyContent: 'center',
+          })}
+        >
+          {state.activePlayers.map((playerId) => {
+            const player = state.playerMetadata[playerId]
+            const score = state.scores[playerId] || 0
+            return (
+              <div
+                key={playerId}
+                className={css({
+                  padding: '8px 16px',
+                  background: 'gray.100',
+                  borderRadius: '8px',
+                  fontSize: 'sm',
+                })}
+              >
+                {player?.emoji} {player?.name}: {score}
+              </div>
+            )
+          })}
+        </div>
+      </div>
+    </div>
+  )
+}

apps/web/src/arcade-games/number-guesser/components/ResultsPhase.tsx

@@ -0,0 +1,208 @@
+/**
+ * Results Phase - Shows winner and final scores
+ */
+
+'use client'
+
+import { css } from '../../../../styled-system/css'
+import { useNumberGuesser } from '../Provider'
+
+export function ResultsPhase() {
+  const { state, goToSetup } = useNumberGuesser()
+
+  const winnerMetadata = state.winner ? state.playerMetadata[state.winner] : null
+  const winnerScore = state.winner ? state.scores[state.winner] : 0
+
+  // Sort players by score
+  const sortedPlayers = [...state.activePlayers].sort((a, b) => {
+    const scoreA = state.scores[a] || 0
+    const scoreB = state.scores[b] || 0
+    return scoreB - scoreA
+  })
+
+  return (
+    <div
+      className={css({
+        padding: '32px',
+        maxWidth: '600px',
+        margin: '0 auto',
+      })}
+    >
+      {/* Winner Celebration */}
+      <div
+        className={css({
+          textAlign: 'center',
+          marginBottom: '32px',
+        })}
+      >
+        <div
+          className={css({
+            fontSize: '96px',
+            marginBottom: '16px',
+            animation: 'bounce 1s ease-in-out infinite',
+          })}
+        >
+          {winnerMetadata?.emoji || '🏆'}
+        </div>
+        <h1
+          className={css({
+            fontSize: '3xl',
+            fontWeight: 'bold',
+            marginBottom: '8px',
+            background: 'linear-gradient(135deg, #fb923c, #f97316)',
+            backgroundClip: 'text',
+            color: 'transparent',
+          })}
+        >
+          {winnerMetadata?.name || 'Someone'} Wins!
+        </h1>
+        <p
+          className={css({
+            fontSize: 'xl',
+            color: 'gray.600',
+          })}
+        >
+          with {winnerScore} {winnerScore === 1 ? 'round' : 'rounds'} won
+        </p>
+      </div>
+
+      {/* Final Standings */}
+      <div
+        className={css({
+          background: 'white',
+          border: '2px solid',
+          borderColor: 'orange.200',
+          borderRadius: '12px',
+          padding: '24px',
+          marginBottom: '24px',
+        })}
+      >
+        <h3
+          className={css({
+            fontSize: 'lg',
+            fontWeight: 'bold',
+            marginBottom: '16px',
+            textAlign: 'center',
+          })}
+        >
+          Final Standings
+        </h3>
+        <div
+          className={css({
+            display: 'flex',
+            flexDirection: 'column',
+            gap: '12px',
+          })}
+        >
+          {sortedPlayers.map((playerId, index) => {
+            const player = state.playerMetadata[playerId]
+            const score = state.scores[playerId] || 0
+            const isWinner = playerId === state.winner
+
+            return (
+              <div
+                key={playerId}
+                className={css({
+                  display: 'flex',
+                  alignItems: 'center',
+                  justifyContent: 'space-between',
+                  padding: '16px',
+                  background: isWinner ? 'linear-gradient(135deg, #fed7aa, #fdba74)' : 'gray.100',
+                  borderRadius: '8px',
+                  border: isWinner ? '2px solid' : 'none',
+                  borderColor: isWinner ? 'orange.300' : undefined,
+                })}
+              >
+                <div
+                  className={css({
+                    display: 'flex',
+                    alignItems: 'center',
+                    gap: '12px',
+                  })}
+                >
+                  <span
+                    className={css({
+                      fontSize: '2xl',
+                      fontWeight: 'bold',
+                      color: 'gray.400',
+                      width: '32px',
+                      textAlign: 'center',
+                    })}
+                  >
+                    {index + 1}
+                  </span>
+                  <span className={css({ fontSize: '32px' })}>{player?.emoji || '🎮'}</span>
+                  <span className={css({ fontSize: 'lg', fontWeight: '600' })}>
+                    {player?.name || 'Unknown'}
+                  </span>
+                </div>
+                <div
+                  className={css({
+                    fontSize: '2xl',
+                    fontWeight: 'bold',
+                    color: isWinner ? 'orange.700' : 'gray.700',
+                  })}
+                >
+                  {score} {isWinner && '🏆'}
+                </div>
+              </div>
+            )
+          })}
+        </div>
+      </div>
+
+      {/* Game Stats */}
+      <div
+        className={css({
+          background: 'white',
+          border: '1px solid',
+          borderColor: 'gray.200',
+          borderRadius: '12px',
+          padding: '16px',
+          marginBottom: '24px',
+          textAlign: 'center',
+        })}
+      >
+        <h3
+          className={css({
+            fontSize: 'md',
+            fontWeight: 'bold',
+            marginBottom: '8px',
+          })}
+        >
+          Game Stats
+        </h3>
+        <p className={css({ color: 'gray.600', fontSize: 'sm' })}>
+          {state.roundNumber} {state.roundNumber === 1 ? 'round' : 'rounds'} played
+        </p>
+        <p className={css({ color: 'gray.600', fontSize: 'sm' })}>
+          {state.guesses.length} {state.guesses.length === 1 ? 'guess' : 'guesses'} made
+        </p>
+      </div>
+
+      {/* Actions */}
+      <button
+        type="button"
+        onClick={goToSetup}
+        className={css({
+          width: '100%',
+          padding: '16px',
+          background: 'linear-gradient(135deg, #fb923c, #f97316)',
+          color: 'white',
+          border: 'none',
+          borderRadius: '12px',
+          fontSize: 'lg',
+          fontWeight: 'bold',
+          cursor: 'pointer',
+          transition: 'all 0.2s',
+          _hover: {
+            transform: 'translateY(-2px)',
+            boxShadow: '0 8px 16px rgba(249, 115, 22, 0.3)',
+          },
+        })}
+      >
+        Play Again
+      </button>
+    </div>
+  )
+}

apps/web/src/arcade-games/number-guesser/components/SetupPhase.tsx

@@ -0,0 +1,197 @@
+/**
+ * Setup Phase - Game configuration
+ */
+
+'use client'
+
+import { css } from '../../../../styled-system/css'
+import { useNumberGuesser } from '../Provider'
+
+export function SetupPhase() {
+  const { state, startGame, setConfig } = useNumberGuesser()
+
+  return (
+    <div
+      className={css({
+        padding: '32px',
+        maxWidth: '600px',
+        margin: '0 auto',
+      })}
+    >
+      <h2
+        className={css({
+          fontSize: '2xl',
+          fontWeight: 'bold',
+          marginBottom: '24px',
+          textAlign: 'center',
+        })}
+      >
+        🎯 Number Guesser Setup
+      </h2>
+
+      <div
+        className={css({
+          background: 'white',
+          border: '2px solid',
+          borderColor: 'orange.200',
+          borderRadius: '12px',
+          padding: '24px',
+          marginBottom: '24px',
+        })}
+      >
+        <h3
+          className={css({
+            fontSize: 'lg',
+            fontWeight: 'bold',
+            marginBottom: '16px',
+          })}
+        >
+          Game Rules
+        </h3>
+        <ul
+          className={css({
+            listStyle: 'disc',
+            paddingLeft: '24px',
+            lineHeight: '1.6',
+            color: 'gray.700',
+          })}
+        >
+          <li>One player chooses a secret number</li>
+          <li>Other players take turns guessing</li>
+          <li>Get feedback on how close your guess is</li>
+          <li>First to guess correctly wins the round!</li>
+          <li>First to {state.roundsToWin} rounds wins the game!</li>
+        </ul>
+      </div>
+
+      <div
+        className={css({
+          background: 'white',
+          border: '2px solid',
+          borderColor: 'orange.200',
+          borderRadius: '12px',
+          padding: '24px',
+          marginBottom: '24px',
+        })}
+      >
+        <h3
+          className={css({
+            fontSize: 'lg',
+            fontWeight: 'bold',
+            marginBottom: '16px',
+          })}
+        >
+          Configuration
+        </h3>
+
+        <div
+          className={css({
+            display: 'flex',
+            flexDirection: 'column',
+            gap: '16px',
+          })}
+        >
+          <div>
+            <label
+              className={css({
+                display: 'block',
+                fontSize: 'sm',
+                fontWeight: '600',
+                marginBottom: '4px',
+              })}
+            >
+              Minimum Number
+            </label>
+            <input
+              type="number"
+              value={state.minNumber ?? 1}
+              onChange={(e) => setConfig('minNumber', Number.parseInt(e.target.value, 10))}
+              className={css({
+                width: '100%',
+                padding: '8px 12px',
+                border: '1px solid',
+                borderColor: 'gray.300',
+                borderRadius: '6px',
+                fontSize: 'md',
+              })}
+            />
+          </div>
+
+          <div>
+            <label
+              className={css({
+                display: 'block',
+                fontSize: 'sm',
+                fontWeight: '600',
+                marginBottom: '4px',
+              })}
+            >
+              Maximum Number
+            </label>
+            <input
+              type="number"
+              value={state.maxNumber ?? 100}
+              onChange={(e) => setConfig('maxNumber', Number.parseInt(e.target.value, 10))}
+              className={css({
+                width: '100%',
+                padding: '8px 12px',
+                border: '1px solid',
+                borderColor: 'gray.300',
+                borderRadius: '6px',
+                fontSize: 'md',
+              })}
+            />
+          </div>
+
+          <div>
+            <label
+              className={css({
+                display: 'block',
+                fontSize: 'sm',
+                fontWeight: '600',
+                marginBottom: '4px',
+              })}
+            >
+              Rounds to Win
+            </label>
+            <input
+              type="number"
+              value={state.roundsToWin ?? 3}
+              onChange={(e) => setConfig('roundsToWin', Number.parseInt(e.target.value, 10))}
+              className={css({
+                width: '100%',
+                padding: '8px 12px',
+                border: '1px solid',
+                borderColor: 'gray.300',
+                borderRadius: '6px',
+                fontSize: 'md',
+              })}
+            />
+          </div>
+        </div>
+      </div>
+
+      <button
+        onClick={startGame}
+        className={css({
+          width: '100%',
+          padding: '16px',
+          background: 'linear-gradient(135deg, #fb923c, #f97316)',
+          color: 'white',
+          border: 'none',
+          borderRadius: '12px',
+          fontSize: 'lg',
+          fontWeight: 'bold',
+          cursor: 'pointer',
+          transition: 'all 0.2s',
+          _hover: {
+            transform: 'translateY(-2px)',
+            boxShadow: '0 8px 16px rgba(249, 115, 22, 0.3)',
+          },
+        })}
+      >
+        Start Game
+      </button>
+    </div>
+  )
+}

apps/web/src/arcade-games/number-guesser/game.yaml

@@ -0,0 +1,15 @@
+name: number-guesser
+displayName: Number Guesser
+icon: 🎯
+description: Classic turn-based number guessing game
+longDescription: One player thinks of a number, others take turns guessing. Get hot/cold feedback as you try to find the secret number. Perfect for testing your deduction skills!
+maxPlayers: 4
+difficulty: Beginner
+chips:
+  - 👥 Multiplayer
+  - 🎲 Turn-Based
+  - 🧠 Logic Puzzle
+color: orange
+gradient: linear-gradient(135deg, #fed7aa, #fdba74)
+borderColor: orange.200
+available: true

apps/web/src/arcade-games/number-guesser/index.ts

@@ -0,0 +1,48 @@
+/**
+ * Number Guesser Game Definition
+ * Exports the complete game using the Arcade SDK
+ */
+
+import { defineGame } from '@/lib/arcade/game-sdk'
+import type { GameManifest } from '@/lib/arcade/game-sdk'
+import { GameComponent } from './components/GameComponent'
+import { NumberGuesserProvider } from './Provider'
+import type { NumberGuesserConfig, NumberGuesserMove, NumberGuesserState } from './types'
+import { numberGuesserValidator } from './Validator'
+
+// Game manifest (matches game.yaml)
+const manifest: GameManifest = {
+  name: 'number-guesser',
+  displayName: 'Number Guesser',
+  icon: '🎯',
+  description: 'Classic turn-based number guessing game',
+  longDescription:
+    'One player thinks of a number, others take turns guessing. Get hot/cold feedback to narrow down your guesses. First to guess wins the round!',
+  maxPlayers: 4,
+  difficulty: 'Beginner',
+  chips: ['👥 Multiplayer', '🎲 Turn-Based', '🧠 Logic Puzzle'],
+  color: 'orange',
+  gradient: 'linear-gradient(135deg, #fed7aa, #fdba74)',
+  borderColor: 'orange.200',
+  available: true,
+}
+
+// Default configuration
+const defaultConfig: NumberGuesserConfig = {
+  minNumber: 1,
+  maxNumber: 100,
+  roundsToWin: 3,
+}
+
+// Export game definition
+export const numberGuesserGame = defineGame<
+  NumberGuesserConfig,
+  NumberGuesserState,
+  NumberGuesserMove
+>({
+  manifest,
+  Provider: NumberGuesserProvider,
+  GameComponent,
+  validator: numberGuesserValidator,
+  defaultConfig,
+})

apps/web/src/arcade-games/number-guesser/types.ts

@@ -0,0 +1,116 @@
+/**
+ * Type definitions for Number Guesser game
+ */
+
+import type { GameMove } from '@/lib/arcade/game-sdk'
+
+/**
+ * Game configuration
+ */
+export type NumberGuesserConfig = {
+  minNumber: number
+  maxNumber: number
+  roundsToWin: number
+}
+
+/**
+ * A single guess attempt
+ */
+export interface Guess {
+  playerId: string
+  playerName: string
+  guess: number
+  distance: number // How far from the secret number
+  timestamp: number
+}
+
+/**
+ * Game phases
+ */
+export type GamePhase = 'setup' | 'choosing' | 'guessing' | 'results'
+
+/**
+ * Game state
+ */
+export type NumberGuesserState = {
+  // Configuration
+  minNumber: number
+  maxNumber: number
+  roundsToWin: number
+
+  // Game phase
+  gamePhase: GamePhase
+
+  // Players
+  activePlayers: string[]
+  playerMetadata: Record<string, { name: string; emoji: string; color: string; userId: string }>
+
+  // Current round
+  secretNumber: number | null
+  chooser: string // Player ID who chose the number
+  currentGuesser: string // Player ID whose turn it is to guess
+
+  // Round history
+  guesses: Guess[]
+  roundNumber: number
+
+  // Scores
+  scores: Record<string, number>
+
+  // Game state
+  gameStartTime: number | null
+  gameEndTime: number | null
+  winner: string | null
+}
+
+/**
+ * Game moves
+ */
+export interface StartGameMove extends GameMove {
+  type: 'START_GAME'
+  data: {
+    activePlayers: string[]
+    playerMetadata: Record<string, unknown>
+  }
+}
+
+export interface ChooseNumberMove extends GameMove {
+  type: 'CHOOSE_NUMBER'
+  data: {
+    secretNumber: number
+  }
+}
+
+export interface MakeGuessMove extends GameMove {
+  type: 'MAKE_GUESS'
+  data: {
+    guess: number
+    playerName: string
+  }
+}
+
+export interface NextRoundMove extends GameMove {
+  type: 'NEXT_ROUND'
+  data: Record<string, never>
+}
+
+export interface GoToSetupMove extends GameMove {
+  type: 'GO_TO_SETUP'
+  data: Record<string, never>
+}
+
+export interface SetConfigMove extends GameMove {
+  type: 'SET_CONFIG'
+  data: {
+    field: 'minNumber' | 'maxNumber' | 'roundsToWin'
+    value: number
+  }
+}
+
+export type NumberGuesserMove =
+  | StartGameMove
+  | ChooseNumberMove
+  | MakeGuessMove
+  | NextRoundMove
+  | GoToSetupMove
+  | SetConfigMove

apps/web/src/components/GameSelector.tsx

@@ -1,7 +1,9 @@
 'use client'
 
+import { useMemo } from 'react'
 import { css } from '../../styled-system/css'
 import { useGameMode } from '../contexts/GameModeContext'
+import { getAllGames } from '../lib/arcade/game-registry'
 import { GameCard } from './GameCard'
 
 // Game configuration defining player limits
@@ -70,7 +72,39 @@ export const GAMES_CONFIG = {
   },
 } as const
 
-export type GameType = keyof typeof GAMES_CONFIG
+export type GameType = keyof typeof GAMES_CONFIG | string
+
+/**
+ * Get all games from both legacy config and new registry
+ */
+function getAllGameConfigs() {
+  const legacyGames = Object.entries(GAMES_CONFIG).map(([gameType, config]) => ({
+    gameType,
+    config,
+  }))
+
+  // Get games from registry and transform to legacy format
+  const registryGames = getAllGames().map((gameDef) => ({
+    gameType: gameDef.manifest.name,
+    config: {
+      name: gameDef.manifest.displayName,
+      fullName: gameDef.manifest.displayName,
+      maxPlayers: gameDef.manifest.maxPlayers,
+      description: gameDef.manifest.description,
+      longDescription: gameDef.manifest.longDescription,
+      url: `/arcade/room?game=${gameDef.manifest.name}`, // Registry games load in room
+      icon: gameDef.manifest.icon,
+      chips: gameDef.manifest.chips,
+      color: gameDef.manifest.color,
+      gradient: gameDef.manifest.gradient,
+      borderColor: gameDef.manifest.borderColor,
+      difficulty: gameDef.manifest.difficulty,
+      available: gameDef.manifest.available,
+    },
+  }))
+
+  return [...legacyGames, ...registryGames]
+}
 
 interface GameSelectorProps {
   variant?: 'compact' | 'detailed'
@@ -87,17 +121,17 @@ export function GameSelector({
 }: GameSelectorProps) {
   const { activePlayerCount } = useGameMode()
 
+  // Memoize the combined games list
+  const allGames = useMemo(() => getAllGameConfigs(), [])
+
   return (
     <div
-      className={css(
-        {
-          height: '100%',
-          display: 'flex',
-          flexDirection: 'column',
-          overflow: 'hidden',
-        },
-        className
-      )}
+      className={`${css({
+        height: '100%',
+        display: 'flex',
+        flexDirection: 'column',
+        overflow: 'hidden',
+      })} ${className || ''}`}
     >
       {showHeader && (
         <h3
@@ -125,7 +159,7 @@ export function GameSelector({
           overflow: 'hidden',
         })}
       >
-        {Object.entries(GAMES_CONFIG).map(([gameType, config]) => (
+        {allGames.map(({ gameType, config }) => (
           <GameCard
             key={gameType}
             gameType={gameType as GameType}

apps/web/src/components/nav/AddPlayerButton.tsx

@@ -26,7 +26,7 @@ interface AddPlayerButtonProps {
   // Context-aware: show different content based on room state
   isInRoom?: boolean
   // Game info for room creation
-  gameName?: 'matching' | 'memory-quiz' | 'complement-race'
+  gameName?: string | null
 }
 
 export function AddPlayerButton({
@@ -38,7 +38,7 @@ export function AddPlayerButton({
   activeTab: activeTabProp,
   setActiveTab: setActiveTabProp,
   isInRoom = false,
-  gameName = 'Arcade',
+  gameName = null,
 }: AddPlayerButtonProps) {
   const popoverRef = React.useRef<HTMLDivElement>(null)
   const router = useRouter()

apps/web/src/components/nav/GameContextNav.tsx

@@ -28,7 +28,7 @@ interface NetworkPlayer {
 interface ArcadeRoomInfo {
   roomId?: string
   roomName?: string
-  gameName: string
+  gameName: string | null
   playerCount: number
   joinCode?: string
 }
@@ -200,6 +200,7 @@ export function GameContextNav({
             onSetup={onSetup}
             onNewGame={onNewGame}
             onQuit={onExitSession}
+            showMenu={true}
           />
           <div style={{ marginLeft: 'auto' }}>
             <GameModeIndicator
@@ -287,7 +288,7 @@ export function GameContextNav({
                   playerScores={playerScores}
                   playerStreaks={playerStreaks}
                   roomId={roomInfo?.roomId}
-                  currentUserId={currentUserId}
+                  currentUserId={currentUserId ?? undefined}
                   isCurrentUserHost={isCurrentUserHost}
                 />
               ))}

apps/web/src/components/nav/JoinRoomModal.tsx

@@ -1,8 +1,8 @@
 import { useEffect, useState } from 'react'
 import { io } from 'socket.io-client'
 import { Modal } from '@/components/common/Modal'
-import type { schema } from '@/db'
-import { useRoomData } from '@/hooks/useRoomData'
+import type { RoomData } from '@/hooks/useRoomData'
+import { useGetRoomByCode, useJoinRoom } from '@/hooks/useRoomData'
 
 export interface JoinRoomModalProps {
   /**
@@ -25,12 +25,13 @@ export interface JoinRoomModalProps {
  * Modal for joining a room by entering a 6-character code
  */
 export function JoinRoomModal({ isOpen, onClose, onSuccess }: JoinRoomModalProps) {
-  const { getRoomByCode, joinRoom } = useRoomData()
+  const { mutateAsync: getRoomByCode } = useGetRoomByCode()
+  const { mutateAsync: joinRoom } = useJoinRoom()
   const [code, setCode] = useState('')
   const [password, setPassword] = useState('')
   const [error, setError] = useState('')
   const [isLoading, setIsLoading] = useState(false)
-  const [roomInfo, setRoomInfo] = useState<schema.ArcadeRoom | null>(null)
+  const [roomInfo, setRoomInfo] = useState<RoomData | null>(null)
   const [needsPassword, setNeedsPassword] = useState(false)
   const [needsApproval, setNeedsApproval] = useState(false)
   const [approvalRequested, setApprovalRequested] = useState(false)
@@ -101,7 +102,7 @@ export function JoinRoomModal({ isOpen, onClose, onSuccess }: JoinRoomModalProps
       }
 
       // Join the room (with password if needed)
-      await joinRoom(room.id, password || undefined)
+      await joinRoom({ roomId: room.id, password: password || undefined })
 
       // Success! Close modal
       handleClose()
@@ -174,7 +175,7 @@ export function JoinRoomModal({ isOpen, onClose, onSuccess }: JoinRoomModalProps
           if (data.roomId === roomInfo.id) {
             console.log('[JoinRoomModal] Joining room automatically...')
             try {
-              await joinRoom(roomInfo.id)
+              await joinRoom({ roomId: roomInfo.id })
               handleClose()
               onSuccess?.()
             } catch (err) {

apps/web/src/components/nav/ModerationPanel.tsx

@@ -1,7 +1,8 @@
 import * as Dialog from '@radix-ui/react-dialog'
 import { useEffect, useState } from 'react'
 import { Modal } from '@/components/common/Modal'
-import type { RoomBan, RoomMember, RoomReport } from '@/db/schema'
+import type { RoomBan, RoomReport } from '@/db/schema'
+import type { RoomMember } from '@/hooks/useRoomData'
 
 export interface RoomPlayer {
   id: string

apps/web/src/components/nav/PlayerConfigDialog.tsx

@@ -52,7 +52,7 @@ export function PlayerConfigDialog({ playerId, onClose }: PlayerConfigDialogProp
   const handleGenerateNewName = () => {
     const allPlayers = Array.from(players.values())
     const existingNames = allPlayers.filter((p) => p.id !== playerId).map((p) => p.name)
-    const newName = generateUniquePlayerName(existingNames)
+    const newName = generateUniquePlayerName(existingNames, player.emoji)
 
     setLocalName(newName)
     updatePlayer(playerId, { name: newName })

apps/web/src/components/nav/RecentRoomsList.tsx

@@ -4,7 +4,7 @@ import { getRoomDisplayWithEmoji } from '@/utils/room-display'
 interface RecentRoom {
   code: string
   name: string | null
-  gameName: string
+  gameName: string | null
   joinedAt: number
 }
 
@@ -105,7 +105,7 @@ export function RecentRoomsList({ onSelectRoom }: RecentRoomsListProps) {
                 {getRoomDisplayWithEmoji({
                   name: room.name,
                   code: room.code,
-                  gameName: room.gameName,
+                  gameName: room.gameName ?? undefined,
                 })}
               </span>
             </div>
@@ -133,7 +133,7 @@ export function RecentRoomsList({ onSelectRoom }: RecentRoomsListProps) {
 export function addToRecentRooms(room: {
   code: string
   name: string | null
-  gameName: string
+  gameName: string | null
 }): void {
   try {
     const stored = localStorage.getItem(STORAGE_KEY)

apps/web/src/contexts/GameModeContext.tsx

@@ -11,7 +11,7 @@ import {
 } from '@/hooks/useUserPlayers'
 import { useViewerId } from '@/hooks/useViewerId'
 import { getNextPlayerColor } from '../types/player'
-import { generateUniquePlayerName, generateUniquePlayerNames } from '../utils/playerNames'
+import { generateUniquePlayerName } from '../utils/playerNames'
 
 // Client-side Player type (compatible with old type)
 export interface Player {
@@ -141,8 +141,13 @@ export function GameModeProvider({ children }: { children: ReactNode }) {
   useEffect(() => {
     if (!isLoading && !isInitialized) {
       if (dbPlayers.length === 0) {
-        // Generate unique names for default players
-        const generatedNames = generateUniquePlayerNames(DEFAULT_PLAYER_CONFIGS.length)
+        // Generate unique names for default players, themed by their emoji
+        const existingNames: string[] = []
+        const generatedNames = DEFAULT_PLAYER_CONFIGS.map((config) => {
+          const name = generateUniquePlayerName(existingNames, config.emoji)
+          existingNames.push(name)
+          return name
+        })
 
         // Create default players with generated names
         DEFAULT_PLAYER_CONFIGS.forEach((config, index) => {
@@ -167,10 +172,11 @@ export function GameModeProvider({ children }: { children: ReactNode }) {
   const addPlayer = (playerData?: Partial<Player>) => {
     const playerList = Array.from(players.values())
     const existingNames = playerList.map((p) => p.name)
+    const emoji = playerData?.emoji ?? '🎮'
 
     const newPlayer = {
-      name: playerData?.name ?? generateUniquePlayerName(existingNames),
-      emoji: playerData?.emoji ?? '🎮',
+      name: playerData?.name ?? generateUniquePlayerName(existingNames, emoji),
+      emoji,
       color: playerData?.color ?? getNextPlayerColor(playerList),
       isActive: playerData?.isActive ?? false,
     }
@@ -254,8 +260,13 @@ export function GameModeProvider({ children }: { children: ReactNode }) {
       deletePlayer(player.id)
     })
 
-    // Generate unique names for default players
-    const generatedNames = generateUniquePlayerNames(DEFAULT_PLAYER_CONFIGS.length)
+    // Generate unique names for default players, themed by their emoji
+    const existingNames: string[] = []
+    const generatedNames = DEFAULT_PLAYER_CONFIGS.map((config) => {
+      const name = generateUniquePlayerName(existingNames, config.emoji)
+      existingNames.push(name)
+      return name
+    })
 
     // Create default players with generated names
     DEFAULT_PLAYER_CONFIGS.forEach((config, index) => {

apps/web/src/db/schema/arcade-rooms.ts

@@ -33,9 +33,8 @@ export const arcadeRooms = sqliteTable('arcade_rooms', {
   displayPassword: text('display_password', { length: 100 }), // Plain text password for display to room owner
 
   // Game configuration (nullable to support game selection in room)
-  gameName: text('game_name', {
-    enum: ['matching', 'memory-quiz', 'complement-race'],
-  }),
+  // Accepts any string - validation happens at runtime against validator registry
+  gameName: text('game_name'),
   gameConfig: text('game_config', { mode: 'json' }), // Game-specific settings (nullable when no game selected)
 
   // Current state

apps/web/src/db/schema/arcade-sessions.ts

@@ -16,9 +16,8 @@ export const arcadeSessions = sqliteTable('arcade_sessions', {
     .references(() => users.id, { onDelete: 'cascade' }),
 
   // Session metadata
-  currentGame: text('current_game', {
-    enum: ['matching', 'memory-quiz', 'complement-race'],
-  }).notNull(),
+  // Accepts any string - validation happens at runtime against validator registry
+  currentGame: text('current_game').notNull(),
 
   gameUrl: text('game_url').notNull(), // e.g., '/arcade/matching'
 

apps/web/src/db/schema/index.ts

@@ -15,5 +15,6 @@ export * from './room-invitations'
 export * from './room-reports'
 export * from './room-bans'
 export * from './room-join-requests'
+export * from './room-game-configs'
 export * from './user-stats'
 export * from './users'

apps/web/src/db/schema/room-game-configs.ts

@@ -0,0 +1,49 @@
+import { createId } from '@paralleldrive/cuid2'
+import { integer, sqliteTable, text, uniqueIndex } from 'drizzle-orm/sqlite-core'
+import { arcadeRooms } from './arcade-rooms'
+
+/**
+ * Game-specific configuration settings for arcade rooms
+ * Each row represents one game's settings for one room
+ */
+export const roomGameConfigs = sqliteTable(
+  'room_game_configs',
+  {
+    id: text('id')
+      .primaryKey()
+      .$defaultFn(() => createId()),
+
+    // Room reference
+    roomId: text('room_id')
+      .notNull()
+      .references(() => arcadeRooms.id, { onDelete: 'cascade' }),
+
+    // Game identifier
+    // Accepts any string - validation happens at runtime against validator registry
+    gameName: text('game_name').notNull(),
+
+    // Game-specific configuration JSON
+    // Structure depends on gameName:
+    // - matching: { gameType, difficulty, turnTimer }
+    // - memory-quiz: { selectedCount, displayTime, selectedDifficulty, playMode }
+    // - complement-race: TBD
+    // - number-guesser: { minNumber, maxNumber, roundsToWin }
+    // - math-sprint: { difficulty, questionsPerRound, timePerQuestion }
+    config: text('config', { mode: 'json' }).notNull(),
+
+    // Timestamps
+    createdAt: integer('created_at', { mode: 'timestamp' })
+      .notNull()
+      .$defaultFn(() => new Date()),
+    updatedAt: integer('updated_at', { mode: 'timestamp' })
+      .notNull()
+      .$defaultFn(() => new Date()),
+  },
+  (table) => ({
+    // Ensure only one config per game per room
+    uniqueRoomGame: uniqueIndex('room_game_idx').on(table.roomId, table.gameName),
+  })
+)
+
+export type RoomGameConfig = typeof roomGameConfigs.$inferSelect
+export type NewRoomGameConfig = typeof roomGameConfigs.$inferInsert

apps/web/src/hooks/useArcadeSession.ts

@@ -46,6 +46,11 @@ export interface UseArcadeSessionReturn<TState> {
    */
   hasPendingMoves: boolean
 
+  /**
+   * Last error from server (move rejection)
+   */
+  lastError: string | null
+
   /**
    * Send a game move (applies optimistically and sends to server)
    * Note: playerId must be provided by caller (not omitted)
@@ -57,6 +62,11 @@ export interface UseArcadeSessionReturn<TState> {
    */
   exitSession: () => void
 
+  /**
+   * Clear the last error
+   */
+  clearError: () => void
+
   /**
    * Manually sync with server (useful after reconnect)
    */
@@ -172,8 +182,10 @@ export function useArcadeSession<TState>(
     version: optimistic.version,
     connected,
     hasPendingMoves: optimistic.hasPendingMoves,
+    lastError: optimistic.lastError,
     sendMove,
     exitSession,
+    clearError: optimistic.clearError,
     refresh,
   }
 }

apps/web/src/hooks/useOptimisticGameState.ts

@@ -46,6 +46,11 @@ export interface UseOptimisticGameStateReturn<TState> {
    */
   hasPendingMoves: boolean
 
+  /**
+   * Last error from server (move rejection)
+   */
+  lastError: string | null
+
   /**
    * Apply a move optimistically and send to server
    */
@@ -66,6 +71,11 @@ export interface UseOptimisticGameStateReturn<TState> {
    */
   syncWithServer: (serverState: TState, serverVersion: number) => void
 
+  /**
+   * Clear the last error
+   */
+  clearError: () => void
+
   /**
    * Reset to initial state
    */
@@ -94,6 +104,9 @@ export function useOptimisticGameState<TState>(
   // Pending moves that haven't been confirmed by server yet
   const [pendingMoves, setPendingMoves] = useState<PendingMove<TState>[]>([])
 
+  // Last error from move rejection
+  const [lastError, setLastError] = useState<string | null>(null)
+
   // Ref for callbacks to avoid stale closures
   const callbacksRef = useRef({ onMoveAccepted, onMoveRejected })
   useEffect(() => {
@@ -152,6 +165,9 @@ export function useOptimisticGameState<TState>(
   )
 
   const handleMoveRejected = useCallback((error: string, rejectedMove: GameMove) => {
+    // Set the error for UI display
+    setLastError(error)
+
     // Remove the rejected move and all subsequent moves from pending queue
     setPendingMoves((prev) => {
       const index = prev.findIndex(
@@ -176,20 +192,27 @@ export function useOptimisticGameState<TState>(
     setPendingMoves([])
   }, [])
 
+  const clearError = useCallback(() => {
+    setLastError(null)
+  }, [])
+
   const reset = useCallback(() => {
     setServerState(initialState)
     setServerVersion(1)
     setPendingMoves([])
+    setLastError(null)
   }, [initialState])
 
   return {
     state: currentState,
     version: serverVersion,
     hasPendingMoves: pendingMoves.length > 0,
+    lastError,
     applyOptimisticMove,
     handleMoveAccepted,
     handleMoveRejected,
     syncWithServer,
+    clearError,
     reset,
   }
 }

apps/web/src/hooks/useRoomData.ts

@@ -449,7 +449,7 @@ export function useRoomData() {
     const handleRoomGameChanged = (data: {
       roomId: string
       gameName: string | null
-      gameConfig: Record<string, unknown>
+      gameConfig?: Record<string, unknown>
     }) => {
       console.log('[useRoomData] Room game changed:', data)
       if (data.roomId === roomData?.id) {
@@ -458,6 +458,8 @@ export function useRoomData() {
           return {
             ...prev,
             gameName: data.gameName,
+            // Only update gameConfig if it was provided in the broadcast
+            ...(data.gameConfig !== undefined ? { gameConfig: data.gameConfig } : {}),
           }
         })
       }
@@ -585,13 +587,20 @@ async function setRoomGameApi(params: {
   gameName: string
   gameConfig?: Record<string, unknown>
 }): Promise<void> {
+  // Only include gameConfig in the request if it was explicitly provided
+  // Otherwise, we preserve the existing gameConfig in the database
+  const body: { gameName: string; gameConfig?: Record<string, unknown> } = {
+    gameName: params.gameName,
+  }
+
+  if (params.gameConfig !== undefined) {
+    body.gameConfig = params.gameConfig
+  }
+
   const response = await fetch(`/api/arcade/rooms/${params.roomId}/settings`, {
     method: 'PATCH',
     headers: { 'Content-Type': 'application/json' },
-    body: JSON.stringify({
-      gameName: params.gameName,
-      gameConfig: params.gameConfig || {},
-    }),
+    body: JSON.stringify(body),
   })
 
   if (!response.ok) {
@@ -625,6 +634,8 @@ export function useSetRoomGame() {
 
 /**
  * Clear/reset game for a room (host only)
+ * This only clears gameName (returns to game selection) but preserves gameConfig
+ * so settings persist when the user selects a game again.
  */
 async function clearRoomGameApi(roomId: string): Promise<void> {
   const response = await fetch(`/api/arcade/rooms/${roomId}/settings`, {
@@ -632,7 +643,7 @@ async function clearRoomGameApi(roomId: string): Promise<void> {
     headers: { 'Content-Type': 'application/json' },
     body: JSON.stringify({
       gameName: null,
-      gameConfig: null,
+      // DO NOT send gameConfig: null - we want to preserve settings!
     }),
   })
 
@@ -672,6 +683,18 @@ async function updateGameConfigApi(params: {
   roomId: string
   gameConfig: Record<string, unknown>
 }): Promise<void> {
+  console.log(
+    '[updateGameConfigApi] Sending PATCH to server:',
+    JSON.stringify(
+      {
+        url: `/api/arcade/rooms/${params.roomId}/settings`,
+        gameConfig: params.gameConfig,
+      },
+      null,
+      2
+    )
+  )
+
   const response = await fetch(`/api/arcade/rooms/${params.roomId}/settings`, {
     method: 'PATCH',
     headers: { 'Content-Type': 'application/json' },
@@ -682,8 +705,11 @@ async function updateGameConfigApi(params: {
 
   if (!response.ok) {
     const errorData = await response.json()
+    console.error('[updateGameConfigApi] Server error:', JSON.stringify(errorData, null, 2))
     throw new Error(errorData.error || 'Failed to update game config')
   }
+
+  console.log('[updateGameConfigApi] Server responded OK')
 }
 
 /**
@@ -704,7 +730,10 @@ export function useUpdateGameConfig() {
           gameConfig: variables.gameConfig,
         }
       })
-      console.log('[useUpdateGameConfig] Updated cache with new gameConfig:', variables.gameConfig)
+      console.log(
+        '[useUpdateGameConfig] Updated cache with new gameConfig:',
+        JSON.stringify(variables.gameConfig, null, 2)
+      )
     },
   })
 }

apps/web/src/lib/arcade/game-config-helpers.ts

@@ -0,0 +1,236 @@
+/**
+ * Game configuration helpers
+ *
+ * Centralized functions for reading and writing game configs from the database.
+ * Uses the room_game_configs table (one row per game per room).
+ */
+
+import { and, eq } from 'drizzle-orm'
+import { createId } from '@paralleldrive/cuid2'
+import { db, schema } from '@/db'
+import type { GameName } from './validators'
+import type { GameConfigByName } from './game-configs'
+import {
+  DEFAULT_MATCHING_CONFIG,
+  DEFAULT_MEMORY_QUIZ_CONFIG,
+  DEFAULT_COMPLEMENT_RACE_CONFIG,
+  DEFAULT_NUMBER_GUESSER_CONFIG,
+  DEFAULT_MATH_SPRINT_CONFIG,
+} from './game-configs'
+
+/**
+ * Extended game name type that includes both registered validators and legacy games
+ * TODO: Remove 'complement-race' once migrated to the new modular system
+ */
+type ExtendedGameName = GameName | 'complement-race'
+
+/**
+ * Get default config for a game
+ */
+function getDefaultGameConfig(gameName: ExtendedGameName): GameConfigByName[ExtendedGameName] {
+  switch (gameName) {
+    case 'matching':
+      return DEFAULT_MATCHING_CONFIG
+    case 'memory-quiz':
+      return DEFAULT_MEMORY_QUIZ_CONFIG
+    case 'complement-race':
+      return DEFAULT_COMPLEMENT_RACE_CONFIG
+    case 'number-guesser':
+      return DEFAULT_NUMBER_GUESSER_CONFIG
+    case 'math-sprint':
+      return DEFAULT_MATH_SPRINT_CONFIG
+    default:
+      throw new Error(`Unknown game: ${gameName}`)
+  }
+}
+
+/**
+ * Get game-specific config from database with defaults
+ * Type-safe: returns the correct config type based on gameName
+ */
+export async function getGameConfig<T extends ExtendedGameName>(
+  roomId: string,
+  gameName: T
+): Promise<GameConfigByName[T]> {
+  // Query the room_game_configs table for this specific room+game
+  const configRow = await db.query.roomGameConfigs.findFirst({
+    where: and(
+      eq(schema.roomGameConfigs.roomId, roomId),
+      eq(schema.roomGameConfigs.gameName, gameName)
+    ),
+  })
+
+  // If no config exists, return defaults
+  if (!configRow) {
+    return getDefaultGameConfig(gameName) as GameConfigByName[T]
+  }
+
+  // Merge saved config with defaults to handle missing fields
+  const defaults = getDefaultGameConfig(gameName)
+  return { ...defaults, ...(configRow.config as object) } as GameConfigByName[T]
+}
+
+/**
+ * Set (upsert) a game's config in the database
+ * Creates a new row if it doesn't exist, updates if it does
+ */
+export async function setGameConfig<T extends ExtendedGameName>(
+  roomId: string,
+  gameName: T,
+  config: Partial<GameConfigByName[T]>
+): Promise<void> {
+  const now = new Date()
+
+  // Check if config already exists
+  const existing = await db.query.roomGameConfigs.findFirst({
+    where: and(
+      eq(schema.roomGameConfigs.roomId, roomId),
+      eq(schema.roomGameConfigs.gameName, gameName)
+    ),
+  })
+
+  if (existing) {
+    // Update existing config (merge with existing values)
+    const mergedConfig = { ...(existing.config as object), ...config }
+    await db
+      .update(schema.roomGameConfigs)
+      .set({
+        config: mergedConfig as any,
+        updatedAt: now,
+      })
+      .where(eq(schema.roomGameConfigs.id, existing.id))
+  } else {
+    // Insert new config (merge with defaults)
+    const defaults = getDefaultGameConfig(gameName)
+    const mergedConfig = { ...defaults, ...config }
+
+    await db.insert(schema.roomGameConfigs).values({
+      id: createId(),
+      roomId,
+      gameName,
+      config: mergedConfig as any,
+      createdAt: now,
+      updatedAt: now,
+    })
+  }
+
+  console.log(`[GameConfig] Updated ${gameName} config for room ${roomId}`)
+}
+
+/**
+ * Update a specific field in a game's config
+ * Convenience wrapper around setGameConfig
+ */
+export async function updateGameConfigField<
+  T extends ExtendedGameName,
+  K extends keyof GameConfigByName[T],
+>(roomId: string, gameName: T, field: K, value: GameConfigByName[T][K]): Promise<void> {
+  // Create a partial config with just the field being updated
+  const partialConfig: Partial<GameConfigByName[T]> = {} as any
+  ;(partialConfig as any)[field] = value
+  await setGameConfig(roomId, gameName, partialConfig)
+}
+
+/**
+ * Delete a game's config from the database
+ * Useful when clearing game selection or cleaning up
+ */
+export async function deleteGameConfig(roomId: string, gameName: ExtendedGameName): Promise<void> {
+  await db
+    .delete(schema.roomGameConfigs)
+    .where(
+      and(eq(schema.roomGameConfigs.roomId, roomId), eq(schema.roomGameConfigs.gameName, gameName))
+    )
+
+  console.log(`[GameConfig] Deleted ${gameName} config for room ${roomId}`)
+}
+
+/**
+ * Get all game configs for a room (all games)
+ * Returns a map of gameName -> config
+ */
+export async function getAllGameConfigs(
+  roomId: string
+): Promise<Partial<Record<ExtendedGameName, unknown>>> {
+  const configs = await db.query.roomGameConfigs.findMany({
+    where: eq(schema.roomGameConfigs.roomId, roomId),
+  })
+
+  const result: Partial<Record<ExtendedGameName, unknown>> = {}
+  for (const config of configs) {
+    result[config.gameName as ExtendedGameName] = config.config
+  }
+
+  return result
+}
+
+/**
+ * Delete all game configs for a room
+ * Called when deleting a room (cascade should handle this, but useful for explicit cleanup)
+ */
+export async function deleteAllGameConfigs(roomId: string): Promise<void> {
+  await db.delete(schema.roomGameConfigs).where(eq(schema.roomGameConfigs.roomId, roomId))
+  console.log(`[GameConfig] Deleted all configs for room ${roomId}`)
+}
+
+/**
+ * Validate a game config at runtime
+ * Returns true if the config is valid for the given game
+ */
+export function validateGameConfig(gameName: ExtendedGameName, config: any): boolean {
+  switch (gameName) {
+    case 'matching':
+      return (
+        typeof config === 'object' &&
+        config !== null &&
+        ['abacus-numeral', 'complement-pairs'].includes(config.gameType) &&
+        typeof config.difficulty === 'number' &&
+        [6, 8, 12, 15].includes(config.difficulty) &&
+        typeof config.turnTimer === 'number' &&
+        config.turnTimer >= 5 &&
+        config.turnTimer <= 300
+      )
+
+    case 'memory-quiz':
+      return (
+        typeof config === 'object' &&
+        config !== null &&
+        [2, 5, 8, 12, 15].includes(config.selectedCount) &&
+        typeof config.displayTime === 'number' &&
+        config.displayTime > 0 &&
+        ['beginner', 'easy', 'medium', 'hard', 'expert'].includes(config.selectedDifficulty) &&
+        ['cooperative', 'competitive'].includes(config.playMode)
+      )
+
+    case 'complement-race':
+      // TODO: Add validation when complement-race settings are defined
+      return typeof config === 'object' && config !== null
+
+    case 'number-guesser':
+      return (
+        typeof config === 'object' &&
+        config !== null &&
+        typeof config.minNumber === 'number' &&
+        typeof config.maxNumber === 'number' &&
+        typeof config.roundsToWin === 'number' &&
+        config.minNumber >= 1 &&
+        config.maxNumber > config.minNumber &&
+        config.roundsToWin >= 1
+      )
+
+    case 'math-sprint':
+      return (
+        typeof config === 'object' &&
+        config !== null &&
+        ['easy', 'medium', 'hard'].includes(config.difficulty) &&
+        typeof config.questionsPerRound === 'number' &&
+        typeof config.timePerQuestion === 'number' &&
+        config.questionsPerRound >= 5 &&
+        config.questionsPerRound <= 20 &&
+        config.timePerQuestion >= 10
+      )
+
+    default:
+      return false
+  }
+}

apps/web/src/lib/arcade/game-configs.ts

@@ -0,0 +1,115 @@
+/**
+ * Shared game configuration types
+ *
+ * This is the single source of truth for all game settings.
+ * These types are used across:
+ * - Database storage (room_game_configs table)
+ * - Validators (getInitialState method signatures)
+ * - Client providers (settings UI and state management)
+ * - Helper functions (reading/writing configs)
+ */
+
+import type { DifficultyLevel } from '@/app/arcade/memory-quiz/types'
+import type { Difficulty, GameType } from '@/app/games/matching/context/types'
+import type { Difficulty as MathSprintDifficulty } from '@/arcade-games/math-sprint/types'
+
+/**
+ * Configuration for matching (memory pairs) game
+ */
+export interface MatchingGameConfig {
+  gameType: GameType
+  difficulty: Difficulty
+  turnTimer: number
+}
+
+/**
+ * Configuration for memory-quiz (soroban lightning) game
+ */
+export interface MemoryQuizGameConfig {
+  selectedCount: 2 | 5 | 8 | 12 | 15
+  displayTime: number
+  selectedDifficulty: DifficultyLevel
+  playMode: 'cooperative' | 'competitive'
+}
+
+/**
+ * Configuration for complement-race game
+ * TODO: Define when implementing complement-race settings
+ */
+export interface ComplementRaceGameConfig {
+  // Future settings will go here
+  placeholder?: never
+}
+
+/**
+ * Configuration for number-guesser game
+ */
+export interface NumberGuesserGameConfig {
+  minNumber: number
+  maxNumber: number
+  roundsToWin: number
+}
+
+/**
+ * Configuration for math-sprint game
+ */
+export interface MathSprintGameConfig {
+  difficulty: MathSprintDifficulty
+  questionsPerRound: number
+  timePerQuestion: number
+}
+
+/**
+ * Union type of all game configs for type-safe access
+ */
+export type GameConfigByName = {
+  matching: MatchingGameConfig
+  'memory-quiz': MemoryQuizGameConfig
+  'complement-race': ComplementRaceGameConfig
+  'number-guesser': NumberGuesserGameConfig
+  'math-sprint': MathSprintGameConfig
+}
+
+/**
+ * Room's game configuration object (nested by game name)
+ * This matches the structure stored in room_game_configs table
+ */
+export interface RoomGameConfig {
+  matching?: MatchingGameConfig
+  'memory-quiz'?: MemoryQuizGameConfig
+  'complement-race'?: ComplementRaceGameConfig
+  'number-guesser'?: NumberGuesserGameConfig
+  'math-sprint'?: MathSprintGameConfig
+}
+
+/**
+ * Default configurations for each game
+ */
+export const DEFAULT_MATCHING_CONFIG: MatchingGameConfig = {
+  gameType: 'abacus-numeral',
+  difficulty: 6,
+  turnTimer: 30,
+}
+
+export const DEFAULT_MEMORY_QUIZ_CONFIG: MemoryQuizGameConfig = {
+  selectedCount: 5,
+  displayTime: 2.0,
+  selectedDifficulty: 'easy',
+  playMode: 'cooperative',
+}
+
+export const DEFAULT_COMPLEMENT_RACE_CONFIG: ComplementRaceGameConfig = {
+  // Future defaults will go here
+}
+
+export const DEFAULT_NUMBER_GUESSER_CONFIG: NumberGuesserGameConfig = {
+  minNumber: 1,
+  maxNumber: 100,
+  roundsToWin: 3,
+}
+
+export const DEFAULT_MATH_SPRINT_CONFIG: MathSprintGameConfig = {
+  difficulty: 'medium',
+  questionsPerRound: 10,
+  timePerQuestion: 30,
+}

apps/web/src/lib/arcade/game-registry.ts

@@ -0,0 +1,113 @@
+/**
+ * Game Registry
+ *
+ * Central registry for all arcade games.
+ * Games are explicitly registered here after being defined.
+ */
+
+import type { GameConfig, GameDefinition, GameMove, GameState } from './game-sdk/types'
+
+/**
+ * Global game registry
+ * Maps game name to game definition
+ * Using `any` for generics to allow different game types
+ */
+const registry = new Map<string, GameDefinition<any, any, any>>()
+
+/**
+ * Register a game in the registry
+ *
+ * @param game - Game definition to register
+ * @throws Error if game with same name already registered
+ */
+export function registerGame<
+  TConfig extends GameConfig,
+  TState extends GameState,
+  TMove extends GameMove,
+>(game: GameDefinition<TConfig, TState, TMove>): void {
+  const { name } = game.manifest
+
+  if (registry.has(name)) {
+    throw new Error(`Game "${name}" is already registered`)
+  }
+
+  // Verify validator is also registered server-side
+  try {
+    const { hasValidator, getValidator } = require('./validators')
+    if (!hasValidator(name)) {
+      console.error(
+        `⚠️  Game "${name}" registered but validator not found in server registry!` +
+          `\n   Add to src/lib/arcade/validators.ts to enable multiplayer.`
+      )
+    } else {
+      const serverValidator = getValidator(name)
+      if (serverValidator !== game.validator) {
+        console.warn(
+          `⚠️  Game "${name}" has different validator instances (client vs server).` +
+            `\n   This may cause issues. Ensure both use the same import.`
+        )
+      }
+    }
+  } catch (error) {
+    // If validators.ts can't be imported (e.g., in browser), skip check
+    // This is expected - validator registry is isomorphic but check only runs server-side
+  }
+
+  registry.set(name, game)
+  console.log(`✅ Registered game: ${name}`)
+}
+
+/**
+ * Get a game from the registry
+ *
+ * @param gameName - Internal game identifier
+ * @returns Game definition or undefined if not found
+ */
+export function getGame(gameName: string): GameDefinition<any, any, any> | undefined {
+  return registry.get(gameName)
+}
+
+/**
+ * Get all registered games
+ *
+ * @returns Array of all game definitions
+ */
+export function getAllGames(): GameDefinition<any, any, any>[] {
+  return Array.from(registry.values())
+}
+
+/**
+ * Get all available games (where available: true)
+ *
+ * @returns Array of available game definitions
+ */
+export function getAvailableGames(): GameDefinition<any, any, any>[] {
+  return getAllGames().filter((game) => game.manifest.available)
+}
+
+/**
+ * Check if a game is registered
+ *
+ * @param gameName - Internal game identifier
+ * @returns true if game is registered
+ */
+export function hasGame(gameName: string): boolean {
+  return registry.has(gameName)
+}
+
+/**
+ * Clear all games from registry (used for testing)
+ */
+export function clearRegistry(): void {
+  registry.clear()
+}
+
+// ============================================================================
+// Game Registrations
+// ============================================================================
+
+import { numberGuesserGame } from '@/arcade-games/number-guesser'
+import { mathSprintGame } from '@/arcade-games/math-sprint'
+
+registerGame(numberGuesserGame)
+registerGame(mathSprintGame)

apps/web/src/lib/arcade/game-sdk/GameErrorBoundary.tsx

@@ -0,0 +1,124 @@
+/**
+ * Error Boundary for Arcade Games
+ *
+ * Catches errors in game components and displays a friendly error message
+ * instead of crashing the entire app.
+ */
+
+'use client'
+
+import { Component, type ReactNode } from 'react'
+
+interface Props {
+  children: ReactNode
+  gameName?: string
+}
+
+interface State {
+  hasError: boolean
+  error?: Error
+}
+
+export class GameErrorBoundary extends Component<Props, State> {
+  constructor(props: Props) {
+    super(props)
+    this.state = { hasError: false }
+  }
+
+  static getDerivedStateFromError(error: Error): State {
+    return {
+      hasError: true,
+      error,
+    }
+  }
+
+  componentDidCatch(error: Error, errorInfo: unknown) {
+    console.error('Game error:', error, errorInfo)
+  }
+
+  render() {
+    if (this.state.hasError) {
+      return (
+        <div
+          style={{
+            display: 'flex',
+            flexDirection: 'column',
+            alignItems: 'center',
+            justifyContent: 'center',
+            padding: '40px',
+            textAlign: 'center',
+            minHeight: '400px',
+            background: 'linear-gradient(135deg, #fef2f2, #fee2e2)',
+          }}
+        >
+          <div
+            style={{
+              fontSize: '64px',
+              marginBottom: '20px',
+            }}
+          >
+            ⚠️
+          </div>
+          <h2
+            style={{
+              fontSize: '24px',
+              fontWeight: 'bold',
+              marginBottom: '12px',
+              color: '#dc2626',
+            }}
+          >
+            Game Error
+          </h2>
+          <p
+            style={{
+              fontSize: '16px',
+              color: '#6b7280',
+              marginBottom: '12px',
+              maxWidth: '500px',
+            }}
+          >
+            {this.props.gameName
+              ? `There was an error loading the game "${this.props.gameName}".`
+              : 'There was an error loading the game.'}
+          </p>
+          {this.state.error && (
+            <pre
+              style={{
+                background: '#f9fafb',
+                border: '1px solid #e5e7eb',
+                borderRadius: '8px',
+                padding: '16px',
+                marginTop: '12px',
+                maxWidth: '600px',
+                overflow: 'auto',
+                textAlign: 'left',
+                fontSize: '12px',
+                color: '#374151',
+              }}
+            >
+              {this.state.error.message}
+            </pre>
+          )}
+          <button
+            onClick={() => window.location.reload()}
+            style={{
+              marginTop: '24px',
+              padding: '12px 24px',
+              background: '#3b82f6',
+              color: 'white',
+              border: 'none',
+              borderRadius: '8px',
+              fontSize: '14px',
+              fontWeight: '600',
+              cursor: 'pointer',
+            }}
+          >
+            Reload Page
+          </button>
+        </div>
+      )
+    }
+
+    return this.props.children
+  }
+}

apps/web/src/lib/arcade/game-sdk/define-game.ts

@@ -0,0 +1,80 @@
+/**
+ * Game definition helper
+ * Provides type-safe game registration
+ */
+
+import type {
+  GameComponent,
+  GameConfig,
+  GameDefinition,
+  GameMove,
+  GameProviderComponent,
+  GameState,
+  GameValidator,
+} from './types'
+import type { GameManifest } from '../manifest-schema'
+
+/**
+ * Options for defining a game
+ */
+export interface DefineGameOptions<
+  TConfig extends GameConfig,
+  TState extends GameState,
+  TMove extends GameMove,
+> {
+  /** Game manifest (loaded from game.yaml) */
+  manifest: GameManifest
+
+  /** React provider component */
+  Provider: GameProviderComponent
+
+  /** Main game UI component */
+  GameComponent: GameComponent
+
+  /** Server-side validator */
+  validator: GameValidator<TState, TMove>
+
+  /** Default configuration for the game */
+  defaultConfig: TConfig
+}
+
+/**
+ * Define a game with full type safety
+ *
+ * This helper ensures all required parts of a game are provided
+ * and returns a properly typed GameDefinition.
+ *
+ * @example
+ * ```typescript
+ * export const myGame = defineGame({
+ *   manifest: loadManifest('./game.yaml'),
+ *   Provider: MyGameProvider,
+ *   GameComponent: MyGameComponent,
+ *   validator: myGameValidator,
+ *   defaultConfig: {
+ *     difficulty: 'easy',
+ *     maxTime: 60
+ *   }
+ * })
+ * ```
+ */
+export function defineGame<
+  TConfig extends GameConfig,
+  TState extends GameState,
+  TMove extends GameMove,
+>(options: DefineGameOptions<TConfig, TState, TMove>): GameDefinition<TConfig, TState, TMove> {
+  const { manifest, Provider, GameComponent, validator, defaultConfig } = options
+
+  // Validate that manifest.name matches the game identifier
+  if (!manifest.name) {
+    throw new Error('Game manifest must have a "name" field')
+  }
+
+  return {
+    manifest,
+    Provider,
+    GameComponent,
+    validator,
+    defaultConfig,
+  }
+}

apps/web/src/lib/arcade/game-sdk/index.ts

@@ -0,0 +1,92 @@
+/**
+ * Arcade Game SDK - Stable API Surface
+ *
+ * This is the ONLY module that games are allowed to import from.
+ * All game code must use this SDK - no direct imports from /src/
+ *
+ * @example
+ * ```typescript
+ * import {
+ *   defineGame,
+ *   useArcadeSession,
+ *   useRoomData,
+ *   type GameDefinition
+ * } from '@/lib/arcade/game-sdk'
+ * ```
+ */
+
+// ============================================================================
+// Core Types
+// ============================================================================
+export type {
+  GameDefinition,
+  GameProviderComponent,
+  GameComponent,
+  GameValidator,
+  GameConfig,
+  GameState,
+  GameMove,
+  ValidationContext,
+  ValidationResult,
+  TeamMoveSentinel,
+} from './types'
+
+export { TEAM_MOVE } from './types'
+
+export type { GameManifest } from '../manifest-schema'
+
+// ============================================================================
+// React Hooks (Controlled API)
+// ============================================================================
+
+/**
+ * Arcade session management hook
+ * Handles state synchronization, move validation, and multiplayer sync
+ */
+export { useArcadeSession } from '@/hooks/useArcadeSession'
+
+/**
+ * Room data hook - access current room information
+ */
+export { useRoomData, useUpdateGameConfig } from '@/hooks/useRoomData'
+
+/**
+ * Game mode context - access players and game mode
+ */
+export { useGameMode } from '@/contexts/GameModeContext'
+
+/**
+ * Viewer ID hook - get current user's ID
+ */
+export { useViewerId } from '@/hooks/useViewerId'
+
+// ============================================================================
+// Utilities
+// ============================================================================
+
+/**
+ * Player ownership and metadata utilities
+ */
+export {
+  buildPlayerMetadata,
+  buildPlayerOwnershipFromRoomData,
+} from '@/lib/arcade/player-ownership.client'
+
+/**
+ * Helper for loading and validating game manifests
+ */
+export { loadManifest } from './load-manifest'
+
+/**
+ * Game definition helper
+ */
+export { defineGame } from './define-game'
+
+// ============================================================================
+// Re-exports for convenience
+// ============================================================================
+
+/**
+ * Common types from contexts
+ */
+export type { Player } from '@/contexts/GameModeContext'

apps/web/src/lib/arcade/game-sdk/load-manifest.ts

@@ -0,0 +1,39 @@
+/**
+ * Manifest loading and validation utilities
+ */
+
+import yaml from 'js-yaml'
+import { readFileSync } from 'fs'
+import { join } from 'path'
+import { validateManifest, type GameManifest } from '../manifest-schema'
+
+/**
+ * Load and validate a game manifest from a YAML file
+ *
+ * @param manifestPath - Absolute path to game.yaml file
+ * @returns Validated GameManifest object
+ * @throws Error if manifest is invalid or file doesn't exist
+ */
+export function loadManifest(manifestPath: string): GameManifest {
+  try {
+    const fileContents = readFileSync(manifestPath, 'utf8')
+    const data = yaml.load(fileContents)
+    return validateManifest(data)
+  } catch (error) {
+    if (error instanceof Error) {
+      throw new Error(`Failed to load manifest from ${manifestPath}: ${error.message}`)
+    }
+    throw error
+  }
+}
+
+/**
+ * Load manifest from a game directory
+ *
+ * @param gameDir - Absolute path to game directory
+ * @returns Validated GameManifest object
+ */
+export function loadManifestFromDir(gameDir: string): GameManifest {
+  const manifestPath = join(gameDir, 'game.yaml')
+  return loadManifest(manifestPath)
+}

apps/web/src/lib/arcade/game-sdk/types.ts

@@ -0,0 +1,80 @@
+/**
+ * Type definitions for the Arcade Game SDK
+ * These types define the contract that all games must implement
+ */
+
+import type { ReactNode } from 'react'
+import type { GameManifest } from '../manifest-schema'
+import type {
+  GameMove as BaseGameMove,
+  GameValidator as BaseGameValidator,
+  ValidationContext,
+  ValidationResult,
+} from '../validation/types'
+
+/**
+ * Re-export base validation types from arcade system
+ */
+export type { GameMove, ValidationContext, ValidationResult } from '../validation/types'
+export { TEAM_MOVE } from '../validation/types'
+export type { TeamMoveSentinel } from '../validation/types'
+
+/**
+ * Generic game configuration
+ * Each game defines its own specific config type
+ */
+export type GameConfig = Record<string, unknown>
+
+/**
+ * Generic game state
+ * Each game defines its own specific state type
+ */
+export type GameState = Record<string, unknown>
+
+/**
+ * Game validator interface
+ * Games must implement this to validate moves server-side
+ */
+export interface GameValidator<TState = GameState, TMove extends BaseGameMove = BaseGameMove>
+  extends BaseGameValidator<TState, TMove> {
+  validateMove(state: TState, move: TMove, context?: ValidationContext): ValidationResult
+  isGameComplete(state: TState): boolean
+  getInitialState(config: unknown): TState
+}
+
+/**
+ * Provider component interface
+ * Each game provides a React context provider that wraps the game UI
+ */
+export type GameProviderComponent = (props: { children: ReactNode }) => JSX.Element
+
+/**
+ * Main game component interface
+ * The root component that renders the game UI
+ */
+export type GameComponent = () => JSX.Element
+
+/**
+ * Complete game definition
+ * This is what games export after using defineGame()
+ */
+export interface GameDefinition<
+  TConfig extends GameConfig = GameConfig,
+  TState extends GameState = GameState,
+  TMove extends BaseGameMove = BaseGameMove,
+> {
+  /** Parsed and validated manifest */
+  manifest: GameManifest
+
+  /** React provider component */
+  Provider: GameProviderComponent
+
+  /** Main game UI component */
+  GameComponent: GameComponent
+
+  /** Server-side validator */
+  validator: GameValidator<TState, TMove>
+
+  /** Default configuration */
+  defaultConfig: TConfig
+}

apps/web/src/lib/arcade/manifest-schema.ts

@@ -0,0 +1,38 @@
+/**
+ * Game manifest schema validation
+ * Validates game.yaml files using Zod
+ */
+
+import { z } from 'zod'
+
+/**
+ * Schema for game manifest (game.yaml)
+ */
+export const GameManifestSchema = z.object({
+  name: z.string().min(1).describe('Internal game identifier (e.g., "matching")'),
+  displayName: z.string().min(1).describe('Display name shown to users'),
+  icon: z.string().min(1).describe('Emoji icon for the game'),
+  description: z.string().min(1).describe('Short description'),
+  longDescription: z.string().min(1).describe('Detailed description'),
+  maxPlayers: z.number().int().min(1).max(10).describe('Maximum number of players'),
+  difficulty: z
+    .enum(['Beginner', 'Intermediate', 'Advanced', 'Expert'])
+    .describe('Difficulty level'),
+  chips: z.array(z.string()).describe('Feature chips displayed on game card'),
+  color: z.string().min(1).describe('Color theme (e.g., "purple")'),
+  gradient: z.string().min(1).describe('CSS gradient for card background'),
+  borderColor: z.string().min(1).describe('Border color (e.g., "purple.200")'),
+  available: z.boolean().describe('Whether game is available to play'),
+})
+
+/**
+ * Inferred TypeScript type from schema
+ */
+export type GameManifest = z.infer<typeof GameManifestSchema>
+
+/**
+ * Validate a parsed manifest object
+ */
+export function validateManifest(data: unknown): GameManifest {
+  return GameManifestSchema.parse(data)
+}

apps/web/src/lib/arcade/session-manager.ts

@@ -6,7 +6,8 @@
 import { eq } from 'drizzle-orm'
 import { db, schema } from '@/db'
 import { buildPlayerOwnershipMap, type PlayerOwnershipMap } from './player-ownership'
-import { type GameMove, type GameName, getValidator } from './validation'
+import { getValidator, type GameName } from './validators'
+import type { GameMove } from './validation/types'
 
 export interface CreateSessionOptions {
   userId: string // User who owns/created the session (typically room creator)

apps/web/src/lib/arcade/validation/MatchingGameValidator.ts

@@ -3,15 +3,10 @@
  * Validates all game moves and state transitions
  */
 
-import type {
-  Difficulty,
-  GameCard,
-  GameType,
-  MemoryPairsState,
-  Player,
-} from '@/app/games/matching/context/types'
+import type { GameCard, MemoryPairsState, Player } from '@/app/games/matching/context/types'
 import { generateGameCards } from '@/app/games/matching/utils/cardGeneration'
 import { canFlipCard, validateMatch } from '@/app/games/matching/utils/matchValidation'
+import type { MatchingGameConfig } from '@/lib/arcade/game-configs'
 import type { GameValidator, MatchingGameMove, ValidationResult } from './types'
 
 export class MatchingGameValidator implements GameValidator<MemoryPairsState, MatchingGameMove> {
@@ -536,11 +531,7 @@ export class MatchingGameValidator implements GameValidator<MemoryPairsState, Ma
     return state.gamePhase === 'results' || state.matchedPairs === state.totalPairs
   }
 
-  getInitialState(config: {
-    difficulty: Difficulty
-    gameType: GameType
-    turnTimer: number
-  }): MemoryPairsState {
+  getInitialState(config: MatchingGameConfig): MemoryPairsState {
     return {
       cards: [],
       gameCards: [],

apps/web/src/lib/arcade/validation/MemoryQuizGameValidator.ts

@@ -3,7 +3,8 @@
  * Validates all game moves and state transitions
  */
 
-import type { DifficultyLevel, SorobanQuizState } from '@/app/arcade/memory-quiz/types'
+import type { SorobanQuizState } from '@/app/arcade/memory-quiz/types'
+import type { MemoryQuizGameConfig } from '@/lib/arcade/game-configs'
 import type {
   GameValidator,
   MemoryQuizGameMove,
@@ -180,12 +181,6 @@ export class MemoryQuizGameValidator
     }
 
     // Number must be in correct answers
-    console.log('[MemoryQuizValidator] Checking number:', {
-      number,
-      correctAnswers: state.correctAnswers,
-      includes: state.correctAnswers.includes(number),
-    })
-
     if (!state.correctAnswers.includes(number)) {
       return {
         valid: false,
@@ -401,11 +396,7 @@ export class MemoryQuizGameValidator
     return state.gamePhase === 'results'
   }
 
-  getInitialState(config: {
-    selectedCount: number
-    displayTime: number
-    selectedDifficulty: DifficultyLevel
-  }): SorobanQuizState {
+  getInitialState(config: MemoryQuizGameConfig): SorobanQuizState {
     return {
       cards: [],
       quizCards: [],
@@ -422,7 +413,7 @@ export class MemoryQuizGameValidator
       activePlayers: [],
       playerMetadata: {},
       playerScores: {},
-      playMode: 'cooperative',
+      playMode: config.playMode || 'cooperative',
       numberFoundBy: {},
       // UI state
       gamePhase: 'setup',

apps/web/src/lib/arcade/validation/index.ts

@@ -1,26 +1,19 @@
 /**
  * Game validator registry
- * Maps game names to their validators
+ * @deprecated This file now re-exports from the unified registry
+ * New code should import from '@/lib/arcade/validators' instead
  */
 
-import { matchingGameValidator } from './MatchingGameValidator'
-import { memoryQuizGameValidator } from './MemoryQuizGameValidator'
-import type { GameName, GameValidator } from './types'
+// Re-export everything from unified registry
+export {
+  getValidator,
+  hasValidator,
+  getRegisteredGameNames,
+  validatorRegistry,
+  matchingGameValidator,
+  memoryQuizGameValidator,
+  numberGuesserValidator,
+} from '../validators'
 
-const validators = new Map<GameName, GameValidator>([
-  ['matching', matchingGameValidator],
-  ['memory-quiz', memoryQuizGameValidator],
-  // Add other game validators here as they're implemented
-])
-
-export function getValidator(gameName: GameName): GameValidator {
-  const validator = validators.get(gameName)
-  if (!validator) {
-    throw new Error(`No validator found for game: ${gameName}`)
-  }
-  return validator
-}
-
-export { matchingGameValidator } from './MatchingGameValidator'
-export { memoryQuizGameValidator } from './MemoryQuizGameValidator'
+export type { GameName } from '../validators'
 export * from './types'

apps/web/src/lib/arcade/validation/types.ts

@@ -6,7 +6,11 @@
 import type { MemoryPairsState } from '@/app/games/matching/context/types'
 import type { SorobanQuizState } from '@/app/arcade/memory-quiz/types'
 
-export type GameName = 'matching' | 'memory-quiz' | 'complement-race'
+/**
+ * Game name type - auto-derived from validator registry
+ * @deprecated Import from '@/lib/arcade/validators' instead
+ */
+export type { GameName } from '../validators'
 
 export interface ValidationResult {
   valid: boolean

apps/web/src/lib/arcade/validators.ts

@@ -0,0 +1,100 @@
+/**
+ * Unified Validator Registry (Isomorphic - runs on client AND server)
+ *
+ * This is the single source of truth for game validators.
+ * Both client and server import validators from here.
+ *
+ * To add a new game:
+ * 1. Import the validator
+ * 2. Add to validatorRegistry Map
+ * 3. GameName type will auto-update
+ */
+
+import { matchingGameValidator } from './validation/MatchingGameValidator'
+import { memoryQuizGameValidator } from './validation/MemoryQuizGameValidator'
+import { numberGuesserValidator } from '@/arcade-games/number-guesser/Validator'
+import { mathSprintValidator } from '@/arcade-games/math-sprint/Validator'
+import type { GameValidator } from './validation/types'
+
+/**
+ * Central registry of all game validators
+ * Key: game name (matches manifest.name)
+ * Value: validator instance
+ */
+export const validatorRegistry = {
+  matching: matchingGameValidator,
+  'memory-quiz': memoryQuizGameValidator,
+  'number-guesser': numberGuesserValidator,
+  'math-sprint': mathSprintValidator,
+  // Add new games here - GameName type will auto-update
+} as const
+
+/**
+ * Auto-derived game name type from registry
+ * No need to manually update this!
+ */
+export type GameName = keyof typeof validatorRegistry
+
+/**
+ * Get validator for a game
+ * @throws Error if game not found (fail fast)
+ */
+export function getValidator(gameName: string): GameValidator {
+  const validator = validatorRegistry[gameName as GameName]
+  if (!validator) {
+    throw new Error(
+      `No validator found for game: ${gameName}. ` +
+        `Available games: ${Object.keys(validatorRegistry).join(', ')}`
+    )
+  }
+  return validator
+}
+
+/**
+ * Check if a game has a registered validator
+ */
+export function hasValidator(gameName: string): gameName is GameName {
+  return gameName in validatorRegistry
+}
+
+/**
+ * Get all registered game names
+ */
+export function getRegisteredGameNames(): GameName[] {
+  return Object.keys(validatorRegistry) as GameName[]
+}
+
+/**
+ * Validate a game name at runtime
+ * Use this instead of TypeScript enums to check if a game is valid
+ *
+ * @param gameName - Game name to validate
+ * @returns true if game has a registered validator
+ */
+export function isValidGameName(gameName: unknown): gameName is GameName {
+  return typeof gameName === 'string' && hasValidator(gameName)
+}
+
+/**
+ * Assert that a game name is valid, throw if not
+ *
+ * @param gameName - Game name to validate
+ * @throws Error if game name is invalid
+ */
+export function assertValidGameName(gameName: unknown): asserts gameName is GameName {
+  if (!isValidGameName(gameName)) {
+    throw new Error(
+      `Invalid game name: ${gameName}. Must be one of: ${getRegisteredGameNames().join(', ')}`
+    )
+  }
+}
+
+/**
+ * Re-export validators for backwards compatibility
+ */
+export {
+  matchingGameValidator,
+  memoryQuizGameValidator,
+  numberGuesserValidator,
+  mathSprintValidator,
+}

apps/web/src/socket-server.ts

@@ -13,8 +13,9 @@ import {
 import { createRoom, getRoomById } from './lib/arcade/room-manager'
 import { getRoomMembers, getUserRooms, setMemberOnline } from './lib/arcade/room-membership'
 import { getRoomActivePlayers, getRoomPlayerIds } from './lib/arcade/player-manager'
-import type { GameMove, GameName } from './lib/arcade/validation'
-import { getValidator } from './lib/arcade/validation'
+import { getValidator, type GameName } from './lib/arcade/validators'
+import type { GameMove } from './lib/arcade/validation/types'
+import { getGameConfig } from './lib/arcade/game-config-helpers'
 
 // Use globalThis to store socket.io instance to avoid module isolation issues
 // This ensures the same instance is accessible across dynamic imports
@@ -81,24 +82,9 @@ export function initializeSocketServer(httpServer: HTTPServer) {
               const validator = getValidator(room.gameName as GameName)
               console.log('[join-arcade-session] Got validator for:', room.gameName)
 
-              // Different games have different initial configs
-              let initialState: any
-              if (room.gameName === 'matching') {
-                initialState = validator.getInitialState({
-                  difficulty: (room.gameConfig as any)?.difficulty || 6,
-                  gameType: (room.gameConfig as any)?.gameType || 'abacus-numeral',
-                  turnTimer: (room.gameConfig as any)?.turnTimer || 30,
-                })
-              } else if (room.gameName === 'memory-quiz') {
-                initialState = validator.getInitialState({
-                  selectedCount: (room.gameConfig as any)?.selectedCount || 5,
-                  displayTime: (room.gameConfig as any)?.displayTime || 2.0,
-                  selectedDifficulty: (room.gameConfig as any)?.selectedDifficulty || 'easy',
-                })
-              } else {
-                // Fallback for other games
-                initialState = validator.getInitialState(room.gameConfig || {})
-              }
+              // Get game-specific config from database (type-safe)
+              const gameConfig = await getGameConfig(roomId, room.gameName as GameName)
+              const initialState = validator.getInitialState(gameConfig)
 
               session = await createArcadeSession({
                 userId,

apps/web/src/utils/__tests__/playerNames.test.ts

@@ -47,7 +47,7 @@ describe('playerNames', () => {
     it('should append number if all combinations are exhausted', () => {
       // Create a mock with limited attempts
       const existingNames = ['Swift Ninja']
-      const name = generateUniquePlayerName(existingNames, 1)
+      const name = generateUniquePlayerName(existingNames, undefined, 1)
 
       // Should either be unique or have a number appended
       expect(name).toBeTruthy()

apps/web/src/utils/playerNames.ts

@@ -1,8 +1,14 @@
 /**
  * Fun automatic player name generation system
  * Generates creative names by combining adjectives with nouns/roles
+ *
+ * Supports avatar-specific theming! Each emoji can have its own personality-matched words.
+ * Falls back gracefully: emoji-specific → category → generic abacus theme
  */
 
+import { EMOJI_SPECIFIC_WORDS, EMOJI_TO_THEME, THEMED_WORD_LISTS } from './themedWords'
+
+// Generic abacus-themed words (used as ultimate fallback)
 const ADJECTIVES = [
   // Abacus-themed adjectives
   'Ancient',
@@ -114,32 +120,96 @@ const NOUNS = [
 ]
 
 /**
- * Generate a random player name by combining an adjective and noun
+ * Select a word list tier using weighted random selection
+ * Balanced mix: emoji-specific (50%), category (25%), global abacus (25%)
  */
-export function generatePlayerName(): string {
-  const adjective = ADJECTIVES[Math.floor(Math.random() * ADJECTIVES.length)]
-  const noun = NOUNS[Math.floor(Math.random() * NOUNS.length)]
+function selectWordListTier(emoji: string, wordType: 'adjectives' | 'nouns'): string[] {
+  // Collect available tiers
+  const availableTiers: Array<{ weight: number; words: string[] }> = []
+
+  // Emoji-specific tier (50% preference)
+  const emojiSpecific = EMOJI_SPECIFIC_WORDS[emoji]
+  if (emojiSpecific) {
+    availableTiers.push({ weight: 50, words: emojiSpecific[wordType] })
+  }
+
+  // Category tier (25% preference)
+  const category = EMOJI_TO_THEME[emoji]
+  if (category) {
+    const categoryTheme = THEMED_WORD_LISTS[category]
+    if (categoryTheme) {
+      availableTiers.push({ weight: 25, words: categoryTheme[wordType] })
+    }
+  }
+
+  // Global abacus tier (25% preference)
+  availableTiers.push({ weight: 25, words: wordType === 'adjectives' ? ADJECTIVES : NOUNS })
+
+  // Weighted random selection
+  const totalWeight = availableTiers.reduce((sum, tier) => sum + tier.weight, 0)
+  let random = Math.random() * totalWeight
+
+  for (const tier of availableTiers) {
+    random -= tier.weight
+    if (random <= 0) {
+      return tier.words
+    }
+  }
+
+  // Fallback (should never reach here)
+  return wordType === 'adjectives' ? ADJECTIVES : NOUNS
+}
+
+/**
+ * Generate a random player name by combining an adjective and noun
+ * Optionally themed based on avatar emoji for ultra-personalized names!
+ * Uses per-word-type probabilistic tier selection for natural variety
+ *
+ * @param emoji - Optional emoji avatar to theme the name around
+ * @returns A creative player name like "Grinning Calculator" or "Lightning Smiler"
+ */
+export function generatePlayerName(emoji?: string): string {
+  if (!emoji) {
+    // No emoji provided, use pure abacus theme
+    const adjective = ADJECTIVES[Math.floor(Math.random() * ADJECTIVES.length)]
+    const noun = NOUNS[Math.floor(Math.random() * NOUNS.length)]
+    return `${adjective} ${noun}`
+  }
+
+  // Select tier independently for each word type
+  // This creates natural mixing: adjective might be emoji-specific while noun is global
+  const adjectiveList = selectWordListTier(emoji, 'adjectives')
+  const nounList = selectWordListTier(emoji, 'nouns')
+
+  const adjective = adjectiveList[Math.floor(Math.random() * adjectiveList.length)]
+  const noun = nounList[Math.floor(Math.random() * nounList.length)]
+
   return `${adjective} ${noun}`
 }
 
 /**
  * Generate a unique player name that doesn't conflict with existing players
  * @param existingNames - Array of names already in use
+ * @param emoji - Optional emoji avatar to theme the name around
  * @param maxAttempts - Maximum attempts to find a unique name (default: 50)
  * @returns A unique player name
  */
-export function generateUniquePlayerName(existingNames: string[], maxAttempts = 50): string {
+export function generateUniquePlayerName(
+  existingNames: string[],
+  emoji?: string,
+  maxAttempts = 50
+): string {
   const existingNamesSet = new Set(existingNames.map((name) => name.toLowerCase()))
 
   for (let i = 0; i < maxAttempts; i++) {
-    const name = generatePlayerName()
+    const name = generatePlayerName(emoji)
     if (!existingNamesSet.has(name.toLowerCase())) {
       return name
     }
   }
 
   // Fallback: if we can't find a unique name, append a number
-  const baseName = generatePlayerName()
+  const baseName = generatePlayerName(emoji)
   let counter = 1
   while (existingNamesSet.has(`${baseName} ${counter}`.toLowerCase())) {
     counter++
@@ -150,12 +220,13 @@ export function generateUniquePlayerName(existingNames: string[], maxAttempts =
 /**
  * Generate a batch of unique player names
  * @param count - Number of names to generate
+ * @param emoji - Optional emoji avatar to theme the names around
  * @returns Array of unique player names
  */
-export function generateUniquePlayerNames(count: number): string[] {
+export function generateUniquePlayerNames(count: number, emoji?: string): string[] {
   const names: string[] = []
   for (let i = 0; i < count; i++) {
-    const name = generateUniquePlayerName(names)
+    const name = generateUniquePlayerName(names, emoji)
     names.push(name)
   }
   return names

apps/web/tsconfig.server.json

@@ -19,10 +19,24 @@
     "src/db/schema/**/*.ts",
     "src/db/migrate.ts",
     "src/lib/arcade/**/*.ts",
+    "src/arcade-games/**/Validator.ts",
+    "src/arcade-games/**/types.ts",
     "src/app/games/matching/context/types.ts",
     "src/app/games/matching/utils/cardGeneration.ts",
     "src/app/games/matching/utils/matchValidation.ts",
+    "src/app/arcade/memory-quiz/types.ts",
     "src/socket-server.ts"
   ],
-  "exclude": ["node_modules", "dist", "**/*.test.ts", "**/*.test.tsx", "**/*.spec.ts"]
+  "exclude": [
+    "node_modules",
+    "dist",
+    "src/components/**/*",
+    "src/contexts/**/*",
+    "src/hooks/**/*",
+    "src/stories/**/*",
+    "src/utils/**/*",
+    "**/*.test.ts",
+    "**/*.test.tsx",
+    "**/*.spec.ts"
+  ]
 }

package.json

@@ -1,6 +1,6 @@
 {
   "name": "soroban-monorepo",
-  "version": "3.17.3",
+  "version": "4.0.0",
   "private": true,
   "description": "Beautiful Soroban Flashcard Generator - Monorepo",
   "workspaces": [

packages/core/client/browser/node_modules/.bin/tsc

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsc" "$@"
+  exec "$basedir/node"  "$basedir/../typescript/bin/tsc" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsc" "$@"
+  exec node  "$basedir/../typescript/bin/tsc" "$@"
 fi

packages/core/client/browser/node_modules/.bin/tsserver

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsserver" "$@"
+  exec "$basedir/node"  "$basedir/../typescript/bin/tsserver" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsserver" "$@"
+  exec node  "$basedir/../typescript/bin/tsserver" "$@"
 fi

packages/core/client/browser/node_modules/.bin/vite

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.0.0_@types+node@20.0.0/node_modules/vite/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.0.0_@types+node@20.0.0/node_modules/vite/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.0.0_@types+node@20.0.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.4.20_@types+node@20.19.19_terser@5.44.0/node_modules/vite/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.4.20_@types+node@20.19.19_terser@5.44.0/node_modules/vite/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.4.20_@types+node@20.19.19_terser@5.44.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.0.0_@types+node@20.0.0/node_modules/vite/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.0.0_@types+node@20.0.0/node_modules/vite/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.0.0_@types+node@20.0.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.4.20_@types+node@20.19.19_terser@5.44.0/node_modules/vite/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.4.20_@types+node@20.19.19_terser@5.44.0/node_modules/vite/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vite@5.4.20_@types+node@20.19.19_terser@5.44.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/vite@5.0.0_@types+node@20.0.0/node_modules/vite/bin/vite.js" "$@"
+  exec "$basedir/node"  "$basedir/../vite/bin/vite.js" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/vite@5.0.0_@types+node@20.0.0/node_modules/vite/bin/vite.js" "$@"
+  exec node  "$basedir/../vite/bin/vite.js" "$@"
 fi

packages/core/client/browser/node_modules/vite

@@ -1 +1 @@
-../../../../../node_modules/.pnpm/vite@5.0.0_@types+node@20.0.0/node_modules/vite
+../../../../../node_modules/.pnpm/vite@5.4.20_@types+node@20.19.19_terser@5.44.0/node_modules/vite

packages/core/client/node/node_modules/.bin/tsc

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsc" "$@"
+  exec "$basedir/node"  "$basedir/../typescript/bin/tsc" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsc" "$@"
+  exec node  "$basedir/../typescript/bin/tsc" "$@"
 fi

packages/core/client/node/node_modules/.bin/tsserver

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsserver" "$@"
+  exec "$basedir/node"  "$basedir/../typescript/bin/tsserver" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsserver" "$@"
+  exec node  "$basedir/../typescript/bin/tsserver" "$@"
 fi

packages/core/client/node/node_modules/.bin/tsup

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/cli-default.js" "$@"
+  exec "$basedir/node"  "$basedir/../tsup/dist/cli-default.js" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/cli-default.js" "$@"
+  exec node  "$basedir/../tsup/dist/cli-default.js" "$@"
 fi

packages/core/client/node/node_modules/.bin/tsup-node

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/cli-node.js" "$@"
+  exec "$basedir/node"  "$basedir/../tsup/dist/cli-node.js" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/cli-node.js" "$@"
+  exec node  "$basedir/../tsup/dist/cli-node.js" "$@"
 fi

packages/core/client/node/node_modules/.bin/vitest

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules/vitest/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.6.1_@types+node@20.19.19_@vitest+ui@3.2.4_happy-dom@18.0.1_jsdom@27.0.0_postcss@8.5.6__terser@5.44.0/node_modules/vitest/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.6.1_@types+node@20.19.19_@vitest+ui@3.2.4_happy-dom@18.0.1_jsdom@27.0.0_postcss@8.5.6__terser@5.44.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules/vitest/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.6.1_@types+node@20.19.19_@vitest+ui@3.2.4_happy-dom@18.0.1_jsdom@27.0.0_postcss@8.5.6__terser@5.44.0/node_modules/vitest/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.6.1_@types+node@20.19.19_@vitest+ui@3.2.4_happy-dom@18.0.1_jsdom@27.0.0_postcss@8.5.6__terser@5.44.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules/vitest/vitest.mjs" "$@"
+  exec "$basedir/node"  "$basedir/../vitest/vitest.mjs" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules/vitest/vitest.mjs" "$@"
+  exec node  "$basedir/../vitest/vitest.mjs" "$@"
 fi

packages/core/client/node/node_modules/tsup

@@ -1 +1 @@
-../../../../../node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup
+../../../../../node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup

packages/core/client/node/node_modules/vitest

@@ -1 +1 @@
-../../../../../node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules/vitest
+../../../../../node_modules/.pnpm/vitest@1.6.1_@types+node@20.19.19_@vitest+ui@3.2.4_happy-dom@18.0.1_jsdom@27.0.0_postcss@8.5.6__terser@5.44.0/node_modules/vitest

packages/core/client/typescript/node_modules/.bin/tsc

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsc" "$@"
+  exec "$basedir/node"  "$basedir/../typescript/bin/tsc" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsc" "$@"
+  exec node  "$basedir/../typescript/bin/tsc" "$@"
 fi

packages/core/client/typescript/node_modules/.bin/tsserver

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/bin/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules/typescript/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsserver" "$@"
+  exec "$basedir/node"  "$basedir/../typescript/bin/tsserver" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/typescript@5.0.2/node_modules/typescript/bin/tsserver" "$@"
+  exec node  "$basedir/../typescript/bin/tsserver" "$@"
 fi

packages/core/client/typescript/node_modules/.bin/tsup

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/cli-default.js" "$@"
+  exec "$basedir/node"  "$basedir/../tsup/dist/cli-default.js" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/cli-default.js" "$@"
+  exec node  "$basedir/../tsup/dist/cli-default.js" "$@"
 fi

packages/core/client/typescript/node_modules/.bin/tsup-node

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/dist/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/cli-node.js" "$@"
+  exec "$basedir/node"  "$basedir/../tsup/dist/cli-node.js" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup/dist/cli-node.js" "$@"
+  exec node  "$basedir/../tsup/dist/cli-node.js" "$@"
 fi

packages/core/client/typescript/node_modules/.bin/vitest

@@ -6,12 +6,12 @@ case `uname` in
 esac
 
 if [ -z "$NODE_PATH" ]; then
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules/vitest/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.6.1_@types+node@20.19.19_@vitest+ui@3.2.4_happy-dom@18.0.1_jsdom@27.0.0_postcss@8.5.6__terser@5.44.0/node_modules/vitest/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.6.1_@types+node@20.19.19_@vitest+ui@3.2.4_happy-dom@18.0.1_jsdom@27.0.0_postcss@8.5.6__terser@5.44.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules"
 else
-  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules/vitest/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
+  export NODE_PATH="/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.6.1_@types+node@20.19.19_@vitest+ui@3.2.4_happy-dom@18.0.1_jsdom@27.0.0_postcss@8.5.6__terser@5.44.0/node_modules/vitest/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/vitest@1.6.1_@types+node@20.19.19_@vitest+ui@3.2.4_happy-dom@18.0.1_jsdom@27.0.0_postcss@8.5.6__terser@5.44.0/node_modules:/Users/antialias/projects/soroban-abacus-flashcards/node_modules/.pnpm/node_modules:$NODE_PATH"
 fi
 if [ -x "$basedir/node" ]; then
-  exec "$basedir/node"  "$basedir/../../../../../../node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules/vitest/vitest.mjs" "$@"
+  exec "$basedir/node"  "$basedir/../vitest/vitest.mjs" "$@"
 else
-  exec node  "$basedir/../../../../../../node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules/vitest/vitest.mjs" "$@"
+  exec node  "$basedir/../vitest/vitest.mjs" "$@"
 fi

packages/core/client/typescript/node_modules/tsup

@@ -1 +1 @@
-../../../../../node_modules/.pnpm/tsup@7.0.0_typescript@5.0.2/node_modules/tsup
+../../../../../node_modules/.pnpm/tsup@7.3.0_postcss@8.5.6_typescript@5.9.3/node_modules/tsup

packages/core/client/typescript/node_modules/vitest

@@ -1 +1 @@
-../../../../../node_modules/.pnpm/vitest@1.0.0_@types+node@20.0.0_@vitest+ui@3.2.4_jsdom@27.0.0/node_modules/vitest
+../../../../../node_modules/.pnpm/vitest@1.6.1_@types+node@20.19.19_@vitest+ui@3.2.4_happy-dom@18.0.1_jsdom@27.0.0_postcss@8.5.6__terser@5.44.0/node_modules/vitest

pnpm-lock.yaml

@@ -152,6 +152,9 @@ importers:
       jose:
         specifier: ^6.1.0
         version: 6.1.0
+      js-yaml:
+        specifier: ^4.1.0
+        version: 4.1.0
       lucide-react:
         specifier: ^0.294.0
         version: 0.294.0(react@18.3.1)
@@ -185,6 +188,9 @@ importers:
       socket.io-client:
         specifier: ^4.8.1
         version: 4.8.1
+      zod:
+        specifier: ^4.1.12
+        version: 4.1.12
     devDependencies:
       '@playwright/test':
         specifier: ^1.55.1
@@ -210,6 +216,9 @@ importers:
       '@types/better-sqlite3':
         specifier: ^7.6.13
         version: 7.6.13
+      '@types/js-yaml':
+        specifier: ^4.0.9
+        version: 4.0.9
       '@types/node':
         specifier: ^20.0.0
         version: 20.19.19
@@ -3668,6 +3677,9 @@ packages:
   '@types/istanbul-reports@3.0.4':
     resolution: {integrity: sha512-pk2B1NWalF9toCRu6gjBzR69syFjP4Od8WRAX+0mmf9lAjCRicLOWc+ZrxZHx/0XRjotgkF9t6iaMJ+aXcOdZQ==}
 
+  '@types/js-yaml@4.0.9':
+    resolution: {integrity: sha512-k4MGaQl5TGo/iipqb2UDG2UwjXziSWkh0uysQelTlJpX1qGlpUZYm8PnO4DxG1qBomtJUdYJ6qR6xdIah10JLg==}
+
   '@types/jsdom@21.1.7':
     resolution: {integrity: sha512-yOriVnggzrnQ3a9OKOCxaVuSug3w3/SbOj5i7VwXWZEyUNl3bLF9V3MfxGbZKuwqJOQyRfqXyROBB1CoZLFWzA==}
 
@@ -9370,6 +9382,9 @@ packages:
     resolution: {integrity: sha512-AyeEbWOu/TAXdxlV9wmGcR0+yh2j3vYPGOECcIj2S7MkrLyC7ne+oye2BKTItt0ii2PHk4cDy+95+LshzbXnGg==}
     engines: {node: '>=12.20'}
 
+  zod@4.1.12:
+    resolution: {integrity: sha512-JInaHOamG8pt5+Ey8kGmdcAcg3OL9reK8ltczgHTAwNhMys/6ThXHityHxVV2p3fkw/c+MAvBHFVYHFZDmjMCQ==}
+
 snapshots:
 
   '@adobe/css-tools@4.4.4': {}
@@ -13150,6 +13165,8 @@ snapshots:
     dependencies:
       '@types/istanbul-lib-report': 3.0.3
 
+  '@types/js-yaml@4.0.9': {}
+
   '@types/jsdom@21.1.7':
     dependencies:
       '@types/node': 20.19.19
@@ -19382,3 +19399,5 @@ snapshots:
   yocto-queue@0.1.0: {}
 
   yocto-queue@1.2.1: {}
+
+  zod@4.1.12: {}