Backend Interview Challenges
94 challenges94 challenges · 5 free to solve now · code rate limiters, caches, concurrency, distributed systems, and more.
- 1EasyLRU cache (O(1) get/put)Free
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- 2MediumLFU cacheFree
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- 3MediumSliding window rate limiterFree
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- 4MediumToken bucket rate limiterFree
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- 5MediumLeaky bucket rate limiterFree
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- 6EasyIn-memory message queue (FIFO) Premium
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- 7MediumPBKDF2-SHA-256 password hashing Premium
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- 8EasySQL: top-N per group (window fn) Premium
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- 9EasyStructured logger (JSON) Premium
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- 10MediumTCP echo server (raw socket) Premium
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- 11MediumThread-safe bounded queue Premium
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- 12MediumJWT verify + sign (HS256) Premium
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- 13HardLeader election (Bully / Raft-lite) Premium
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- 14EasyMetrics: counter / gauge / histogram Premium
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- 15HardReader-writer lock Premium
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