Challenge Library
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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6 challenges matching your filters
Clear topic filter- Multiple ChoiceHard
Two-phase commit blocking
system-designdistributed-transactions2pc - Multiple ChoiceIntermediate
Saga pattern compensation
system-designdistributed-transactionssaga - Multiple ChoiceIntermediate
Outbox pattern
system-designdistributed-transactionsoutbox - Code AnalysisHard
Outbox without proper relay
system-designoutboxdistributed-transactions - Code AnalysisIntermediate
2PC coordinator down
system-designdistributed-transactions2pc - Code AnalysisHard
Two-phase commit blocking analysis
2pcdistributed-transactionsblocking
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