15-Minute Up/Down Market Hedged Spread Arbitrage

How It Works Multiple repos converge on this strategy: trade Polymarket's short-duration (15-minute) crypto Up/Down binary markets by simultaneously buying both YES and NO when the combined cost is below $1.00 (i.e., the market is mis-summed), or by making spread trades where the bid-ask spread on one side is wide enough to extract profit. The Gamma API is used to discover markets and monitor pricing. Configurable hedge thresholds and risk management parameters control position sizing and maximum exposure.

Entry Conditions Entry fires when: (a) the sum of best YES and NO ask prices is below a configurable threshold (pure arbitrage), or (b) the spread between bid and ask on one side exceeds a minimum profit margin (market-making/spread capture). The hedge threshold parameter allows operators to tune aggressiveness. The 'Spreadmaker' variant explicitly describes maintaining entry cost below a set limit.

Exit Conditions Given 15-minute resolution windows, the primary exit is resolution. The short duration minimizes mark-to-market risk. Early exit may be taken if one leg reprices favorably before resolution.

Verified Results Three separate repos (kenfri13, Corettafinnougricspeaking368, Juanp2389) implement variations of this strategy, suggesting independent convergence on the same edge. The Juanp2389 variant extends this across both Kalshi and Polymarket BTC markets, adding cross-platform arbitrage. No quantified on-chain results are published across any of the three repos.

Risks Polymarket 15-minute markets can have very low liquidity, making fills at target prices unreliable. The arbitrage window on a mis-summed market closes within milliseconds in competitive environments. Simultaneous fill of both legs is not guaranteed, leaving residual directional risk. Crypto volatility within 15-minute windows means the underlying can move against a partially filled position. Cross-platform arbitrage (Kalshi + Polymarket) adds settlement and custody complexity.