System Design
Design: Chat (1:1 + group)
Real-time messaging at scale. Connection model, fanout, push, presence, history.
1 min read·interactive · premium
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- Bottlenecks, failure modes, and why the simple design breaks.
- Capacity math you can reuse in interview answers.
- Trade-offs and ADR-style reasoning, not only a final diagram.
- Saved progress across the system design learning path.
Bundle: system-design-cases