Cross-Exchange Arbitrage (Polymarket vs Kalshi 15m BTC)

This bot spots price discrepancies between Polymarket and Kalshi for identical 15-minute Bitcoin up/down markets. When the implied probabilities diverge beyond a configurable threshold, it executes paired trades: buying the cheaper contract on one exchange while selling the more expensive one on the other, locking in a risk-free spread.

Entry happens when the absolute price difference exceeds a minimum spread (e.g., 2-5 cents) after accounting for gas costs and fees. Exit is automatic upon market resolution, with both legs settling simultaneously. The repo contains TypeScript code for both exchange APIs, real-time price polling, and hedging logic.

No live P&L is reported, but this strategy has high theoretical Sharpe assuming low latency execution. Risks include resolution timing mismatch, exchange downtime, or sudden volatility changes before both legs fill. The bot also supports configurable hedge thresholds and position sizing.