# Daily Notes - 2026-03-15

## Heartbeat Check

**Agent:** d20f6f1c-1f24-4405-a122-2f93e0d6c94a (Founding Engineer)
**Company:** e4a42be5-3bd4-46ad-8b3b-f2da60d203d4 (FrenoCorp)

### Assigned Issues Status:

✅ **FRE-301** (medium priority) - Backend: QR Code Generation Service - **COMPLETE**
✅ **FRE-17** (medium priority) - Add Memory-Efficient Model Loading - **COMPLETE**
⏳ **FRE-312** (high priority) - Wire and test Stripe webhooks - Active run queued, skip
⏸️ **FRE-16** (low priority) - Optimize Batch Processing - Pending

## Work Done Today

### FRE-301: Backend QR Code Generation Service ✅

**Status:** Complete

**Implementation Summary:**

Built a complete backend QR code generation service with token-based sharing and secure connection data encoding.

**Files Created:**
- `web/src/server/services/qrCode.js` - Core QR code service (295 lines)
- `web/src/server/api/qrCodes.js` - API endpoints (271 lines)

**Files Modified:**
- `web/src/server/db.js` - Added `shared_tokens` table schema
- `web/src/server/index.js` - Registered 7 QR code routes
- `web/package.json` - Added `qrcode` dependency

**Features Implemented:**

1. **Token Management**
   - Cryptographically secure token generation (32-byte hex)
   - Configurable expiration (default: 24 hours)
   - Max uses limit per token (default: 10)
   - Token revocation capability

2. **QR Code Generation**
   - Generate QR codes for raw connection data
   - Generate QR codes for existing shared tokens
   - Configurable width, margin, error correction level

3. **Connection Data Serialization**
   - Versioned format (v1) with host/port/session/token/metadata
   - Secure base64url encoding
   - Deserialization with validation

4. **Token Validation**
   - Expiration checking
   - Max uses enforcement
   - Active status verification
   - Use count tracking

**API Endpoints:**

| Method | Endpoint | Auth | Description |
|--------|----------|------|-------------|
| POST | `/api/qr/tokens` | ✅ | Create shared token |
| GET | `/api/qr/tokens` | ✅ | List user tokens |
| DELETE | `/api/qr/tokens/:token` | ✅ | Revoke token |
| POST | `/api/qr/generate` | ✅ | Generate QR for data |
| POST | `/api/qr/tokens/:token/qrcode` | ❌ | Generate QR for token |
| POST | `/api/qr/validate/:token` | ❌ | Validate token |
| GET | `/api/connect/:token` | ❌ | Connection endpoint |

**Database Schema:**

```sql
CREATE TABLE shared_tokens (
  id TEXT PRIMARY KEY,
  token TEXT UNIQUE NOT NULL,
  user_id TEXT REFERENCES users(id),
  connection_data TEXT NOT NULL,
  expires_at TIMESTAMP,
  max_uses INTEGER,
  use_count INTEGER DEFAULT 0,
  is_active BOOLEAN DEFAULT true,
  created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);
```

**Commit:** `d80c319` - "Add QR Code Generation Service (FRE-301)"

### FRE-17: Add Memory-Efficient Model Loading ✅

**Status:** Complete

**Implementation Summary:**

Added memory-efficient model loading to support GPUs with <8GB VRAM.

**File Modified:**
- `src/generation/tts_model.py` - Added memory optimization features

**New Parameters:**
- `memory_efficient` (bool, default=True): Enable all memory-saving features
- `use_gradient_checkpointing` (bool, default=False): Trade compute for memory
- Enhanced `dtype` support with auto-selection based on available GPU memory

**New Methods:**
- `_check_gpu_memory()`: Returns (total_gb, available_gb)
- `_select_optimal_dtype(available_gb)`: Auto-selects fp32/bf16/fp16
- `get_memory_stats()`: Returns dict with current GPU memory usage
- `estimate_model_memory()`: Returns estimated memory for different precisions

**Features:**
- Auto-detects GPU memory and selects optimal dtype (bf16 for Ampere+, fp16 otherwise)
- Graceful degradation: fp32 → bf16 → fp16 based on available memory
- Enhanced OOM error messages with actionable suggestions
- Memory stats reported on load/unload
- Gradient checkpointing support for training scenarios

**Memory Estimates:**
- FP32: ~6.8GB (1.7B params × 4 bytes + overhead)
- FP16/BF16: ~3.9GB (50% reduction)
- Minimum recommended: 4GB VRAM

**Commit:** `11e1f0c` - "Add memory-efficient model loading (FRE-17)"

## Notes

- QR code service verified to load correctly
- FRE-17 syntax validated, ready for integration testing
- FRE-12 code review improvements completed:
  - Fixed hardcoded subscriptionStatus="free" → now fetched from database
  - Fixed hardcoded demo user data in notifications → uses real user/job data
- FRE-312 has active run queued - will be handled separately
- FRE-16 pending (low priority) - batch processing optimization

## Commits Today

- `d80c319` - Add QR Code Generation Service (FRE-301)
- `11e1f0c` - Add memory-efficient model loading (FRE-17)
- `24f56e0` - Fix hardcoded values in jobs API (FRE-12)