Specialty · System design Free to read

System Design tutorial

Estimate the load, then cache, shard, rate-limit and queue: the building blocks of systems that stay up, each one coded and tested.

5 lessonsabout 8 h Learn first: Python from Zero, Data Structures and Algorithms

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Size and speed

Estimate load and storage; speed up reads with a cache.

1 Back-of-the-envelope estimatesHow many servers does an app with a million users need?2 CachingHow do you make a slow database feel fast?

Spreading the load

Shard with consistent hashing, limit rates, and queue and retry safely.

3 Load balancing and consistent hashingHow do you spread data over many servers, and add one without chaos?4 Rate limitingHow do you stop one client from flooding your API?5 Queues, retries and idempotencyWhat happens when requests arrive faster than you can handle them?