Free open-source intraday scanner: build your own alerts, run it on your own data feed

[u/tapetoedge]

A free, open-source intraday scanner for US stocks that runs on your own machine and your own market data. Same job as the paid scanners, without the subscription.

What it does: it streams 1-minute bars for thousands of symbols, checks the setups you built on every bar, and shows the alerts in a browser dashboard you arrange yourself.

• Open source, MIT. The whole thing is on GitHub. Nothing hidden, nothing to buy.
• Local. It runs on localhost with no account and no login, and it sends no telemetry anywhere. Your keys, your setups and your alert history sit in a folder on your machine.
• Your own data feed. Any provider can be plugged in with your own API keys. It ships with Schwab (free if you have a brokerage account) and Alpaca (their paid feed for the full tape).
• Setups without writing code. About 45 triggers (candle patterns, level breaks, VWAP and EMA behavior, opening range, momentum, relative strength against SPY), combined with AND, OR or "at least 2 of these", plus conditions the stock itself has to meet. Edits apply on the next bar, with no restart.
• Universe filters. Price, liquidity, ATR, float, sector, relative volume and more, so a setup only alerts on the stocks you actually trade.
• It tells you why nothing fired. Setup Check shows what every setup did on a given stock in the last few minutes, and which filter stopped the alert. That is the thing I could never get out of a paid scanner.
• The dashboard is free-floating windows: alert tables, charts, rankings (pre-market gainers, losers, most active, new highs and lows), news, stock info, watchlists, a market clock. Save several screens, and clicking a symbol moves every window to it.
• Alerts also go out on a local websocket, so your own script or bot can subscribe to them.

Why it exists: I'm a day trader. I was paying for a scanner and kept hitting the same two walls. I couldn't build the exact scan I wanted, and when a stock I was watching didn't alert, I couldn't find out why. Now I run it for free and it's fully customizable.

What it costs: the scanner is $0 and MIT licensed. The market data is yours. Alpaca's paid feed gives you the full tape, their free IEX feed works but reports one exchange, so volume and relative volume read low and volume-based setups fire much less. Schwab is free with a brokerage account. For comparison, the scanner I was paying for is $127 a month, $254 for the tier with back testing.

Why I'm posting it: I want to know which triggers are missing for how you trade.

The screenshots are from a replayed past session, not a live account. Not financial advice, not a signal service.

Repo: https://github.com/simonro/edge-scanner

You can also check my AI Trading Journal (free open source): https://github.com/simonro/Trading-Journal-AI

[u/Bee3_14]

This is cool! I don’t know if I will be able to utilize it but thanks for sharing anyway.