A system design roadmap with concept lessons
System design opens on a roadmap: a free Foundations trunk, five branches and eight interactive concept lessons, starting with Backpressure.
What changed
The System design page leads with a map drawn like the DSA one. Foundations covers interview formats, how the web works, latency numbers, estimates and API design. Five branches follow: Data, Messaging and streams, Patterns, Scale and reliability, and AI systems.
Eight topics have an interactive lesson with a widget you can change: backpressure, the transactional outbox, idempotency keys, consistent hashing, caching strategies, replication and consistency, rate limiting and RAG pipelines. The other 46 topics are short reads that link the module lessons on the same idea.
Foundations topics and the Backpressure lesson are free. Branch topics come with the Complete pass.
Try it
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