# Technology Stack

## Backend

- **Language**: TypeScript (Node.js)
- **Framework**: Fastify
- **Scraping**: Playwright (headless Chromium)
- **Database**: PostgreSQL + TimescaleDB extension
- **ORM**: Prisma or Drizzle
- **Job Scheduling**: Node Scheduler or BullMQ
- **WebSockets**: Native `ws` or Fastify WS plugin
- **Deployment**: Docker containers

## Frontend (Electron Desktop App)

- **Framework**: Electron 30+
- **UI Library**: NextJS? + TypeScript/TSX
- **Build Tool**: Vite
- **Styling**: TailwindCSS
- **Charts**: Recharts, ECharts, or TradingView Charting Library
- **State Management**: Zustand or Recoil
- **Auto-updates**: electron-updater

## Testing

- **Unit Tests**: Jest
- **E2E Tests**: Playwright
- **API Integration**: Supertest or Pact

## Common Commands

```bash
# Backend
npm run dev          # Start development server
npm run build        # Build TypeScript
npm run test         # Run Jest tests
npm run scrape       # Manual scrape trigger

# Frontend (Electron)
npm run dev          # Start Electron in dev mode
npm run build        # Build production app
npm run package      # Package for distribution
npm run test         # Run tests

# Database
npm run migrate      # Run database migrations
npm run seed         # Seed initial data
```

## Performance Requirements

- API latency < 50ms for standard queries
- Support 5000+ concurrent WebSocket connections
- Desktop app must handle 50k+ chart datapoints smoothly
- Scraping frequency: every 5 minutes (configurable)