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@@ -6,9 +6,10 @@
 
 ## 🎯 CURRENT STATUS
 
-**Phase:** 1.5 (Email & WSDC & Profiles & Security) - ✅ COMPLETED
-**Next Phase:** 2 (Core Features) - ⏳ PENDING
-**Progress:** ~65% complete
+**Phase:** 1.6 (Competition Heats System) - ⏳ IN PROGRESS
+**Previous Phase:** 1.5 (Email & WSDC & Profiles & Security & QR Check-in) - ✅ COMPLETED
+**Next Phase:** 2 (Core Features - Matches API + Ratings + WebRTC) - ⏳ PENDING
+**Progress:** ~68% complete
 
 ### ✅ Completed
 - Phase 0: Frontend mockup with all views
@@ -79,6 +80,118 @@
 
 ---
 
+## 📌 Phase 1.6: Competition Heats System - ⏳ IN PROGRESS
+
+**Estimated Time:** 6-8 hours
+**Priority:** HIGH (blocking for proper matchmaking)
+**Status:** Design phase completed, ready for implementation
+
+### Business Logic Summary
+- Users must declare their competition heats before matchmaking
+- One user can compete in multiple divisions/heats (e.g., J&J Novice + Strictly Advanced)
+- **Constraint:** Cannot compete in same role in same division+competition type (e.g., cannot have "J&J Novice Leader" twice)
+- Role is optional (can be NULL = undeclared)
+- Heat numbers: 1-9
+- Format example: "J&J NOV 1 L" (Jack & Jill, Novice, Heat 1, Leader)
+
+### Step 1: Database Schema (1-2h) ⏳
+- [ ] Create migration for 3 new tables:
+  - `divisions` - Pre-defined competition divisions
+    - Columns: id, name (varchar), abbreviation (varchar 3), display_order (int)
+    - Seed data: Newcomer (NEW), Novice (NOV), Intermediate (INT), Advanced (ADV), All-Star (ALL), Champion (CHA)
+  - `competition_types` - Pre-defined competition types
+    - Columns: id, name (varchar), abbreviation (varchar 3)
+    - Seed data: Jack & Jill (J&J), Strictly (STR)
+  - `event_user_heats` - User's declared heats for event
+    - Columns: id, user_id, event_id, division_id, competition_type_id, heat_number (1-9), role (enum: Leader/Follower/NULL), created_at, updated_at
+    - **UNIQUE constraint:** (user_id, event_id, division_id, competition_type_id, role)
+    - Foreign keys: user_id → users.id, event_id → events.id, division_id → divisions.id, competition_type_id → competition_types.id
+    - Indexes: (user_id, event_id), (event_id)
+- [ ] Update Prisma schema
+- [ ] Run migration
+- [ ] Verify seed data
+
+### Step 2: Backend API (2-3h) ⏳
+- [ ] Create routes and controllers:
+  - `GET /api/divisions` - List all divisions (public)
+  - `GET /api/competition-types` - List all competition types (public)
+  - `POST /api/events/:slug/heats` - Add/update user's heats (authenticated)
+    - Input: array of { divisionId, competitionTypeId, heatNumber, role? }
+    - Validation: unique constraint, heat number 1-9
+    - Replace all existing heats (upsert pattern)
+  - `GET /api/events/:slug/heats/me` - Get current user's heats (authenticated)
+  - `GET /api/events/:slug/heats/all` - Get all users' heats for sidebar (authenticated)
+    - Returns: userId, username, avatar, heats[]
+  - `DELETE /api/events/:slug/heats/:id` - Delete specific heat (authenticated)
+- [ ] Validation middleware:
+  - Heat number 1-9
+  - Role enum (Leader/Follower/NULL)
+  - Unique constraint enforcement
+  - User must be event participant
+- [ ] Unit tests (CRUD operations, validation, constraints)
+
+### Step 3: Socket.IO Events (0.5h) ⏳
+- [ ] Add event: `heats_updated` - Broadcast when user updates heats
+  - Payload: { userId, username, heats[] }
+  - Send to all users in event room
+- [ ] Update active_users event to include heats data
+
+### Step 4: Frontend Components (2-3h) ⏳
+- [ ] Create HeatsBanner component (sticky between header and chat):
+  - Show only if user has no heats declared
+  - Form with dynamic heat entries (add/remove)
+  - Fields per entry: Competition Type (select), Division (select), Heat Number (1-9), Role (optional: Leader/Follower)
+  - "Save Heats" button → POST /api/events/:slug/heats
+  - On save success: hide banner, show success message
+- [ ] Add "Edit Heats" button in EventChatPage header (next to "Leave Event")
+  - Opens modal with same form as banner
+  - Pre-fill with existing heats
+  - "Update Heats" button
+- [ ] Update EventChatPage sidebar (Active Users):
+  - Display heat badges under username
+  - Format: "J&J NOV 1 L", "STR ADV 3" (no role if NULL)
+  - Max 3 visible badges, "+" indicator if more
+  - Add checkbox: "Hide users from my heats"
+    - Logic: Hide users with ANY matching (division + competition_type + heat_number)
+  - Disable UserPlus icon if user has no heats declared
+- [ ] Create frontend API methods in services/api.js:
+  - divisionsAPI.getAll()
+  - competitionTypesAPI.getAll()
+  - heatsAPI.saveHeats(slug, heats[])
+  - heatsAPI.getMyHeats(slug)
+  - heatsAPI.getAllHeats(slug)
+  - heatsAPI.deleteHeat(slug, heatId)
+- [ ] Socket.IO integration:
+  - Listen to `heats_updated` event
+  - Update active users list in real-time
+
+### Step 5: Styling & UX (0.5-1h) ⏳
+- [ ] Heat badges design (color-coded by division?)
+- [ ] Banner responsive design (mobile + desktop)
+- [ ] Modal for editing heats
+- [ ] Loading states for heat operations
+- [ ] Error handling & validation messages
+- [ ] Empty states ("No heats declared yet")
+
+### Step 6: Testing & Edge Cases (0.5-1h) ⏳
+- [ ] Test unique constraint violation (frontend + backend)
+- [ ] Test filter "Hide users from my heats"
+- [ ] Test real-time updates when someone changes heats
+- [ ] Test UserPlus button disabled for users without heats
+- [ ] Test banner dismissal and re-opening via "Edit Heats"
+- [ ] Test multiple heats display in sidebar
+- [ ] Test role optional (NULL) handling
+
+### Technical Notes
+- **Abbreviations:**
+  - Divisions: NEW, NOV, INT, ADV, ALL, CHA
+  - Competition Types: J&J, STR
+  - Roles: L (Leader), F (Follower), empty (NULL)
+- **Display format:** "{CompType} {Div} {Heat} {Role?}" → "J&J NOV 1 L"
+- **Future enhancement:** When Matches API is implemented, editing heats with active match requires partner confirmation
+
+---
+
 ## 📌 NEXT STEPS - Phase 2: Core Features
 
 **Estimated Time:** 12-15 hours