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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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4 challenges matching your filters
Clear topic filter- Multiple ChoiceIntermediate
Connection pool sizing math
connection-poolsizingcapacity - Multiple ChoiceHard
PgBouncer transaction vs session pooling
pgbouncerconnection-poolpostgres - Code AnalysisBeginner
Thundering herd on connection pool resize
system-designdatabasesconnection-pool - Code AnalysisIntermediate
Connection pool exhaustion from leaked connections
connection-poolresource-leakreliability
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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.