shadowspread/polymarket-auto-trading

This is a copy trading bot for Polymarket, a prediction market platform. The idea behind copy trading is straightforward: the bot watches another user's account and automatically places the same trades. When the target account opens a position, the bot opens a matching one in the user's own wallet. When the target closes or exits a position, the bot does the same. The bot is written in TypeScript and runs as a background process. It polls the target account every two seconds by default, compares the current open positions to the previous snapshot, and then submits buy or sell orders to Polymarket's order book when something changes. Users configure it through environment variables in a .env file, specifying the target wallet address, their own private key (if copy trading is enabled), and limits on how large each trade can be in US dollars. There is also a monitoring-only mode that does not place any orders. In this mode, the bot simply prints a formatted list of the target account's open positions every few seconds, showing the market question, share quantity, and current price. A dry-run mode sits between these two: it simulates what orders would be placed without actually submitting them to the blockchain, which is useful for validating behavior before committing real funds. The README is transparent about the tool's current limitations. State is kept only in memory, so restarting the bot may cause it to treat already-open positions as new and resubmit buy orders. A slippage tolerance setting exists in the configuration but is not yet applied to the actual orders posted. Monitoring is done by polling rather than via a live connection, so there is a delay between when the target makes a trade and when the bot detects it. The project requires Node.js 18 or newer and a Polygon wallet with funds to trade. It is released under an MIT license.