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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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3 challenges matching your filters
Clear topic filter- Multiple ChoiceBeginner
When microservices hurt
architecturemicroservicestrade-offs - Multiple ChoiceHard
Local-first software trade-offs
local-firsttrade-offsconsistency - Multiple ChoiceIntermediate
B+tree vs LSM read/write trade-off
btreelsmtrade-offs
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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.