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Coding Challenges
5,893 curated questions across every arena — browse by topic, then jump into a live 3-minute battle to put them to the test.
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32 challenges matching your filters
Clear topic filter- Multiple ChoiceHard
[Redis] 16384 slots Horizontal sharding
qaredisredisqa - Multiple ChoiceHard
[Redis] Hash tags Horizontal sharding
qaredisredisqa - Multiple ChoiceHard
[Redis] MOVED Horizontal sharding
qaredisredisqa - Multiple ChoiceHard
[Redis] ASK Horizontal sharding
qaredisredisqa - Multiple ChoiceHard
[Redis] Min 3 masters Horizontal sharding
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] Hashes Beyond strings
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] Lists Beyond strings
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] Sets Beyond strings
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] Sorted sets Beyond strings
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] Streams Beyond strings
qaredisredisqa - Multiple ChoiceHard
[Redis] lru maxmemory handling
qaredisredisqa - Multiple ChoiceHard
[Redis] lfu maxmemory handling
qaredisredisqa - Multiple ChoiceHard
[Redis] ttl maxmemory handling
qaredisredisqa - Multiple ChoiceHard
[Redis] random maxmemory handling
qaredisredisqa - Multiple ChoiceHard
[Redis] noeviction maxmemory handling
qaredisredisqa - Multiple ChoiceHard
[Redis] RDB RDB and AOF
qaredisredisqa - Multiple ChoiceHard
[Redis] AOF RDB and AOF
qaredisredisqa - Multiple ChoiceHard
[Redis] Hybrid RDB and AOF
qaredisredisqa - Multiple ChoiceHard
[Redis] Rewrite RDB and AOF
qaredisredisqa - Multiple ChoiceHard
[Redis] No persistence RDB and AOF
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] Reduce RTT Batch commands
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] NOT atomic Batch commands
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] MULTI/EXEC Batch commands
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] Performance Batch commands
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] Client queue Batch commands
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] PUBLISH Messaging
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] SUBSCRIBE Messaging
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] PSUBSCRIBE Messaging
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] No persistence Messaging
qaredisredisqa - Multiple ChoiceIntermediate
[Redis] Fire-and-forget Messaging
qaredisredisqa - Code AnalysisIntermediate
Redis distributed lock expiry race
distributed-lockredisfencing - Code AnalysisHard
Hot leaderboard partition on one key
leaderboardhot-partitionredis
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Every challenge here is drawn from the live Code Royale pool. Review a question, then head to the arena to answer under pressure against a real opponent — 3-minute matches, Elo ranking, and badge tiers on the line.