How I Built a Polymarket Trading Bot That Actually Makes Money

Originally published at chudi.dev I spent three months building a trading bot for Polymarket. Not a "signal subscriber" or a wrapper around someone else's strategy — a system that finds mispricing, places orders, and manages exits autonomously with real money on the line. Here is the full architecture: what works, what broke, and what the numbers look like. TL;DR The edge : Polymarket's 5-minute BTC up/down markets lag Binance price moves by 30-90 seconds The strategy : Detect a large BTC move on Binance, buy the corresponding YES/NO market on Polymarket before odds reprice The stack : Python, asyncio, Binance WebSocket, py_clob_client, VPS in Amsterdam The results : 69.6% win rate, +$11.51 net over 23 clean trades (Feb 13-16, 2025) The hardest part : The bugs were silent — wrong API calls that succeeded but destroyed your position Why Prediction Markets Have Exploitable Lags Polymarket runs binary options on events. The 5-minute BTC up/down markets ask: will BTC be higher or lower in