System Design Interview Tutorial

A free tutorial on system design interviews: how the interview runs, the six phases of a strong answer, how to prepare, and the distributed application patterns to reach for in deep dives.

1. The system design interview: How the 60-minute interview runs, what the interviewer scores, the six phases of a strong answer, and a two-week plan to prepare.
2. Application design patterns: A map of distributed application patterns, from low-level primitives to architecture: what each one guarantees, what it costs, and how to choose the smallest design that stays correct.
3. Low-level primitives in depth: How each low-level primitive works, with mechanisms, diagrams, numbers and real systems: CAS, isolation, locks, logs, idempotency, clocks, leases, consensus, quorums, replication, partitioning, 2PC, CRDTs and rate limits.
4. Infrastructure building blocks in depth: How each mid-level building block works: load balancing, retries, circuit breakers, queues, logs, outbox, caches, replicas, sharding, CDNs, mesh, tracing and backups, with diagrams, numbers and real systems.
5. Architectural patterns in depth: A deep reference for every high-level architecture pattern, from CRUD and modular monoliths to sagas, cells and multi-region: how each one works, the numbers behind it, where real systems use it and how it fails.