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System Design Interview Walkthroughs
Six end-to-end walkthroughs: URL shortener (TinyURL), rate limiter, news feed (Twitter/Instagram), chat app (WhatsApp), distributed cache (Redis-style), and a full Uber-style 45-min mock.
Module Content
Walkthrough 1 — Design a URL Shortener (TinyURL)
The classic system design warm-up. Encoding, redirect flow, capacity estimation, hash collisions.
Walkthrough 2 — Design a Rate Limiter
A focused design covering the algorithm choice, distributed counter implementation, and the operational considerations.
Walkthrough 3 — Design a News Feed (Twitter/Instagram)
The canonical 'social network' design: feeds, fan-out, ranking. Includes the celebrity problem and push vs pull trade-offs.
Walkthrough 4 — Design a Chat App (WhatsApp)
Real-time messaging at scale. Connection management, message delivery guarantees, group chats, and end-to-end encryption considerations.
Walkthrough 5 — Design a Distributed Cache (Redis-style)
Building a Redis-like distributed cache from scratch. Consistent hashing, replication, eviction, the operational realities.
Walkthrough 6 — Full 45-Min Mock: Design Uber
A full-length system design mock. Covers location, matching, payments, real-time updates. The most complete walkthrough.