Stock Researcher

Look up any stock and get live fundamentals plus a plain-language AI research brief. A second tab, Trading, runs an ATR-based trend and range signal against the same ticker: current trend, stop loss, buy/sell history, and a backtest.

Stack

• Frontend — React, Tailwind CSS, Recharts, Framer Motion, Lucide icons
• Backend — FastAPI
• Data — Finnhub (fundamentals, quote), Twelve Data (daily OHLC for the Trading tab)
• AI — Claude, for the research brief

Running locally

Backend

cd backend
python3 -m venv venv && source venv/bin/activate
pip install -r requirements.txt --extra-index-url https://d33sy5i8bnduwe.cloudfront.net/simple/
cp .env.example .env   # then fill in ANTHROPIC_API_KEY, FINNHUB_API_KEY, TWELVEDATA_API_KEY
uvicorn server:app --host 0.0.0.0 --port 8001 --reload

Frontend

cd frontend
npm install
npm start

The frontend reads REACT_APP_BACKEND_URL from frontend/.env and calls every backend route under /api.

API

• GET /api/stock/{ticker} — live snapshot: price, 52-week range, market cap, sector, valuation and growth metrics, analyst ratings, 1-year price history. Returns 404 for an invalid ticker.
• POST /api/research — { ticker } → an AI-generated brief (business summary, catalysts, valuation read, risks, moat note) plus two competitor tickers.
• POST /api/competitors — { ticker, tickers? } → USD-normalized snapshots for side-by-side comparison. Pass tickers to skip the AI lookup.
• GET /api/trading/{ticker} — ATR trend and range signal: daily bars with the trend line, current trend, stop loss, full buy/sell signal history, and a backtest (win rate, return, max drawdown, current open position). Returns 404 for an invalid ticker.

Deploying (Render)

This repo includes a render.yaml blueprint that provisions the backend as a web service and the frontend as a static site.

1. Render — sign in at render.com, New → Blueprint, connect this repo. Render reads render.yaml and creates both services.
2. When prompted for environment variables, set on stock-researcher-api:
   • ANTHROPIC_API_KEY — your key from console.anthropic.com
   • FINNHUB_API_KEY — your key from finnhub.io
   • TWELVEDATA_API_KEY — your key from twelvedata.com, free tier is enough to start
   • REDIS_URL — optional but recommended, without it caching falls back to in-memory only and resets whenever the free-tier service sleeps
3. Deploy. Once both services are live, open the static site's URL — that's your app.
4. CORS_ORIGINS and REACT_APP_BACKEND_URL are wired between the two services automatically in the blueprint. If either service can't reach the other after the first deploy, set the missing one manually in that service's Environment tab to the other service's https://...onrender.com URL, then trigger a manual redeploy.

Every push to main after that redeploys both services automatically.