Designing systems that scale, for backend/AI-engineer interviews: the method, the building blocks, and worked case studies.
Tier 1 — master these first: How to Approach a System Design Interview, Back-of-the-Envelope Estimation, Scalability, Availability & Reliability, CDN, Reverse Proxy, Load Balancer, API Gateway, Caching, Message Queue, Database Replication, Sharding, CAP Theorem, Strong vs Eventual Consistency, Idempotency, Consistent Hashing, Fan-out, URL Shortener, Distributed Rate Limiter, Notification System, News Feed, Chat System, Ticket Booking System, ChatGPT, LLM Inference Serving Platform.
Tier 2 — strong understanding: DNS, Microservices, Polling vs Long Polling vs WebSockets vs SSE, Circuit Breaker, Unique ID Generation, Blob Storage & Media Pipelines, Search & Inverted Indexes, Geospatial Indexing, Distributed Key-Value Store, Search Autocomplete, Web Crawler, Video Streaming Platform, File Storage & Sync, Ride-Sharing Service, Payment System, AI Agent Platform, AI Content Moderation System, Image Generation Service.
Tier 3 — learn after these: Bloom Filters, HyperLogLog & Count-Min Sketch, Distributed Job Scheduler, Real-Time Leaderboard.