Design real-time crypto prices homepage
Company: Coinbase
Role: Software Engineer
Category: System Design
Difficulty: hard
Interview Round: Onsite
Design a system that powers a “crypto explore/home” page (like an exchange’s market page) that:
- Shows a list of crypto assets (e.g., BTC, ETH, SOL, …)
- Displays **near real-time price updates** (and optionally 24h change, volume, etc.)
- Updates many concurrent clients efficiently (web + mobile)
Assume you have access to upstream market data (from exchanges/market makers/internal pricing service) that produces frequent ticks.
### What to cover
- Requirements (latency, freshness, accuracy, ordering)
- APIs for initial page load and live updates
- Data ingestion/normalization and internal price computation
- Fanout strategy to clients (WebSockets/SSE/push)
- Storage, caching, and historical needs (optional)
- Scalability, multi-region, reliability, and monitoring
Quick Answer: This question evaluates system design competency for real-time, low-latency data pipelines and client fanout for a crypto prices homepage, testing skills in data ingestion and normalization, streaming updates, API design, caching and storage, scalability, multi-region reliability, and monitoring.