# Technology Stack

**Analysis Date:** 2025-02-23

## Languages

**Primary:**
- Python 3.12 - Backend microservices, data processing, model serving
- TypeScript 5.9 - React frontend, type safety
- JavaScript - React components, utilities

**Secondary:**
- Bash - Docker entrypoints, scripts

## Runtime

**Environment:**
- Python 3.12 runtime (Docker: `python:3.12-slim`)
- Node.js 20 (Docker: `node:20-alpine`)

**Package Manager:**
- pip (Python) with `pyproject.toml` configuration
- npm (Node) with `package.json` and `package-lock.json`
- Lockfile: `package-lock.json` present for frontend

## Frameworks

**Core Backend:**
- FastAPI 0.110+ - HTTP server for API gateway at `services/api_gateway/main.py`
- SQLAlchemy 2.0+ with asyncio - ORM for PostgreSQL at `shared/db.py`
- Alembic 1.13+ - Database migrations in `alembic/` directory
- Uvicorn 0.27+ - ASGI server for FastAPI

**Frontend:**
- React 19.2 - UI framework
- Vite 7.3 - Build tool and dev server
- Tailwind CSS 4.2 - Styling framework
- React Router 7.13 - Client-side routing

**Data & State:**
- TanStack Query 5.90+ - Server state management for API calls
- Axios 1.13+ - HTTP client for backend communication
- Recharts 3.7 - Charts for portfolio analytics
- TradingView lightweight-charts 5.1 - Professional candlestick charts

**Testing:**
- pytest 8.0+ - Python test runner with `asyncio_mode = "auto"`
- pytest-asyncio 0.23+ - Async test support
- pytest-cov 4.1+ - Coverage reporting
- React Testing Library - Frontend component testing (imported but not actively tested)

**Build/Dev:**
- Ruff 0.3+ - Python linter and formatter (line-length: 120)
- MyPy 1.8+ - Python type checker
- TypeScript Compiler (tsc) - TypeScript compilation
- ESLint 9.39+ - JavaScript/TypeScript linting with React hooks and refresh plugins

## Key Dependencies

**Critical Backend:**
- redis 5.0+ - Message broker via Redis Streams at `shared/redis_streams.py`
- asyncpg 0.29+ - PostgreSQL async driver (via SQLAlchemy)
- pydantic 2.0+ - Data validation and settings management at `shared/config.py`
- pydantic-settings 2.0+ - Environment-based configuration

**Machine Learning & NLP:**
- transformers 4.38+ - FinBERT model for sentiment analysis at `services/sentiment_analyzer/analyzers/finbert.py`
- torch 2.2+ - PyTorch runtime for transformers
- ollama 0.1+ - Local LLM inference client (fallback analyzer) at `services/sentiment_analyzer/analyzers/ollama_analyzer.py`

**News & Data Sources:**
- feedparser 6.0+ - RSS feed parsing at `services/news_fetcher/main.py`
- praw 7.7+ - Reddit API client (blocking)
- asyncpraw 7.7+ - Async Reddit API client for non-blocking Reddit fetches
- httpx 0.27+ - Async HTTP client for web requests

**Brokerage Integration:**
- alpaca-py 0.21+ - Alpaca trading API client at `shared/broker/alpaca_broker.py` and `services/market_data/main.py`
  - Provides: Order management, position tracking, market data (bars), account info
  - Used by: Trade executor, market data service, API gateway portfolio sync

**Authentication & Security:**
- webauthn 2.0+ - WebAuthn/passkey registration and verification at `services/api_gateway/auth/routes.py`
- PyJWT 2.8+ with crypto support - JWT token creation/verification at `services/api_gateway/auth/jwt.py`

**Observability:**
- opentelemetry-sdk 1.20+ - Metrics collection framework
- opentelemetry-exporter-prometheus 0.45b+ - Prometheus metrics exporter
- opentelemetry-api 1.20+ - Telemetry instrumentation
- prometheus-client - HTTP metrics server (imported in `shared/telemetry.py`)

**Data Processing:**
- numpy 1.26+ - Numeric operations for backtester
- pandas 2.2+ - Time series data manipulation
- pytz 2024.1+ - Timezone support for market data

**Utilities:**
- websockets 12.0+ - WebSocket support for real-time APIs (in api_gateway optional-dependencies)

## Configuration

**Environment:**
- Pydantic BaseSettings with `TRADING_` prefix for all environment variables
- Service-specific config classes extend `BaseConfig` at:
  - `services/sentiment_analyzer/config.py` - FinBERT threshold, Ollama host
  - `services/news_fetcher/config.py` - RSS feeds, Reddit credentials
  - `services/trade_executor/config.py` - Risk limits, Alpaca credentials
  - `services/api_gateway/config.py` - JWT settings, CORS, WebAuthn RP
  - `services/market_data/config.py` - Watchlist, bar timeframe, poll intervals

**Configuration File:**
- `.env` - Runtime environment variables (not tracked, example: `.env.example`)
- `pyproject.toml` - Project metadata and optional dependency groups:
  - `[api]` - FastAPI, WebAuthn, JWT
  - `[news]` - feedparser, praw, asyncpraw, httpx
  - `[sentiment]` - transformers, torch, ollama
  - `[trading]` - alpaca-py, pytz
  - `[backtester]` - numpy, pandas
  - `[dev]` - pytest, coverage, linters

**Database:**
- PostgreSQL 16 + TimescaleDB extension (Docker: `timescale/timescaledb:latest-pg16`)
- Connection: Async with asyncpg driver
- Migrations: Alembic with `alembic upgrade head` (auto-run at startup)

**Cache/Message Broker:**
- Redis 7-alpine - In-memory data store
- Streams feature for inter-service messaging (consumer groups)
- Persistent volumes for both PostgreSQL and Redis

## Build Configuration

**Backend:**
- `pyproject.toml` - Single source of truth for Python dependencies
- Setuptools 70.0+ - Build backend
- Finds packages under: `shared*`, `services*`, `backtester*`, `scripts*`, `tests*`

**Frontend:**
- `dashboard/vite.config.ts` - Vite configuration with React plugin and Tailwind CSS
- `dashboard/tsconfig.json` - TypeScript configuration (references app and node configs)
- Build: `npm run build` produces static files served by Nginx

**Docker:**
- `docker/Dockerfile.service` - Multi-stage build for all Python services
  - Stage 1: Builder installs dependencies via pip
  - Stage 2: Runtime with slim Python image
- `docker/Dockerfile.dashboard` - Multi-stage Node+Nginx build
  - Stage 1: Node 20 builds Vite app
  - Stage 2: Nginx serves static files
- `docker-compose.yml` - Orchestrates: PostgreSQL, Redis, 7 microservices, dashboard

## Platform Requirements

**Development:**
- Python 3.12 with venv or virtualenv
- Node.js 20+ with npm
- Docker & Docker Compose (for integration tests and full-stack deployment)
- Optional: Ollama (local LLM, defaults to `http://localhost:11434`)

**Production:**
- Docker and Docker Compose
- PostgreSQL 16+ (external managed service or container)
- Redis 7+ (external managed service or container)
- Environment variables set via `.env` file or container environment
- Optional: External Ollama service for sentiment fallback

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*Stack analysis: 2025-02-23*