System Design

Foundations
0 · How to approach a design0/3
1 · Numbers & estimation0/3
Building blocks
2 · Scaling the web tier0/4
3 · Caching0/4
4 · Databases: choosing & replicating0/4
5 · Partitioning & consistency0/4
6 · Async & messaging0/4
7 · The front door: APIs, CDNs, rate limits0/4
8 · Reliability & observability0/4
Case studies
9 · Case: URL shortener0/3
10 · Case: news feed0/3
11 · Case: chat system0/3

11 · Case: chat system · Reference design

Reference design

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