Design a Real-Time Online Chess Platform
Company: OpenAI
Role: Software Engineer
Category: System Design
Difficulty: medium
Interview Round: Technical Screen
Quick Answer: Design the backend for a globally distributed real-time chess platform supporting moves, spectators, clocks, reconnects, and failover. Define authoritative game ownership, idempotent move ordering, durable history, Redis trade-offs, fan-out isolation, and portable clock recovery.