Footgold is an allowlisted football decision lab I built to make forecasting inspectable rather than oracular. It covers 11 competitions and combines point-in-time probabilities, executable Kalshi prices, structured research, a personal decision ledger, and model audits in one operational interface.
The central design constraint is separation. Forecasts use only information available before kickoff; market prices are compared only after the probability is frozen; and qualitative research can change the decision context without silently editing the football model.
I designed and built the product end to end with Next.js, React, TypeScript, Drizzle ORM, Neon Postgres, Clerk, Vercel, OpenAI, Sportmonks, American Soccer Analysis, and Kalshi.
The main interface challenge was turning uncertain evidence into explicit states—action, pass, wait for a lineup, experimental, or fallback—while still exposing probabilities, both sides of a market, fees, expected return, data freshness, and model version.
Each major forecast release ships with an immutable historical audit. Failed or inconclusive experiments stay visible rather than being erased; the current audit explicitly warns when an apparent edge has not translated into a validated wagering signal.
Footgold is experimental decision-support software, not a promise of profitable betting. Its value is the evidence trail: a workflow for screening matches, recording decisions, and learning honestly from later results. The screenshots above use synthetic local data and contain no private account information.