Start by clarifying requirements and scope with the interviewer, then focus on the core real-time gameplay and matchmaking systems, and finally discuss scalability, trade-offs, and product features. Structure your answer around high-level architecture, data models, and key components, while continuously justifying design decisions.
Pro tip: Emphasize the real-time, low-latency nature of chess and how you would handle concurrency and consistency, as these are critical for a seamless user experience. Also, show product sense by mentioning features like puzzles, tournaments, and social aspects that drive engagement.
Ask questions to understand expected scale (DAU, concurrent games), core features (real-time play, matchmaking, ratings, social), and non-functional requirements (latency, consistency, availability).
Outline the main components: client apps, API gateway, game service, matchmaking service, user service, and data stores. Explain how they interact to support real-time gameplay.
Detail the design of critical parts: real-time communication (WebSockets), game state management, matchmaking algorithm (ELO-based), and move validation/anti-cheat.
Describe how to store user profiles, game history, and ratings. Discuss choices like SQL vs NoSQL, caching, and sharding for scalability.
Address scaling to millions of users, handling peak loads, and trade-offs (e.g., consistency vs latency). Also mention additional features like puzzles, tournaments, and social integration.
AI-generated suggestions, not part of the candidate's original notes. May be inaccurate — verify before relying on them.