Sportz: Real-Time Broadcast Platform
A full-stack real-time multi-sport broadcast system delivering live scores and commentary at sub-second latency.
Overview
Sportz is a full-stack real-time broadcast platform (a React frontend and a Node/WebSocket backend, in separate repos) that streams live scores and ball-by-ball commentary at sub-second latency. It's built the way production systems should be: real-time state as a single source of truth, a full test pyramid, end-to-end observability, and hardened APIs. The architecture and its failure modes are written up in a companion engineering handbook (see Sportz Docs).
Features
Live scores and ball-by-ball commentary at sub-second latency via room-scoped pub/sub
Heartbeat-based ghost-connection reaping and exponential-backoff reconnect
Server state unified as a single source of truth: removing an entire fetched-vs-live reconciliation layer
Full test pyramid: 95 backend tests against real databases and live WebSocket pairs, plus e2e with accessibility scanning on production builds
End-to-end observability across browser, backend, and database as a single trace
API hardening: rate limiting, bot detection, and schema validation at every boundary
CI/CD on both repos, a multi-stage non-root Docker backend, and per-PR preview deploys
Key Engineering Decisions
Designed real-time delivery correct by construction: room-scoped pub/sub, ghost-connection reaping, backoff reconnect
Collapsed fetched-vs-live state into one source of truth, deleting a whole class of reconciliation bugs
Made the system observable end to end so a single request is followable browser → backend → DB
Authored a 50+ page handbook of ADRs and production post-mortems as it was built