## Notes - Design a newsfeed - Design Whatsapp - Design Uber - Design YouTube - Design a Distributed Message Queue - Design a CDN - Instagram feed - Twitter timeline - Google Search - Design a payment system - Design S3 ## Prep - Practice - Mock interviews - Understand common patterns - Load balancing - Database sharding - CDN - Caching - Tooling ## Clarifying Questions - Features - Non-functional requirements - Scalability - Technical constraints - Important numbers - Use cases - Scope Also - Explain rationale - Discuss trade-offs