Projects

A Tippspiel — the German office-and-family ritual of predicting football scores against your friends. The incumbents monetise it with ads and betting odds. Tipperoo has neither, and never will.

• Correctness is the product. Scores are provisional until two independent sources reconcile. Results live in an append-only event log, so a corrected result recomputes the table transparently instead of silently rewriting history.
• Rust engine, Next.js web app. A pure outbound worker does ingestion, reconciliation and scoring; Postgres carries the rest through row-level security. No inbound HTTP surface on the engine at all.
• Live without lying. The database emits an opaque signal over Supabase Realtime and the browser refetches durable truth. Scores never travel on the wire, so a dropped message can’t leave you looking at a number that was never real.
• EU-hosted, privacy-first, and free at launch.