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Code RoomAPI rate limiter
EasyPrep Room Coding #3661

API rate limiter

System designNetworking & APIsEntry–Mid~25 min

Design a basic rate limiter for a single public API endpoint so no client can call it more than 100 times per minute. Clients are identified by API key. The API runs on a couple of server instances behind a load balancer. Describe how you count requests and decide when to reject (return 429).

What a strong answer looks like

Clarify scale and constraints first. Propose a clean component breakdown, then go deep on the hard parts (data model, bottlenecks, consistency, failure modes) and name the trade-offs you are making.

Clarify3:00 left
Estimate3:00 planned
Design8:30 planned
Deep dive6:30 planned
Failure4:00 planned
0:00
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.