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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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13 challenges matching your filters
Clear topic filter- Multiple ChoiceBeginner
Transaction outbox in modular monolith
outboxmodular-monolithreliability - Multiple ChoiceIntermediate
Outbox pattern
system-designdistributed-transactionsoutbox - Multiple ChoiceIntermediate
Outbox relay ordering
system-designoutboxmessaging - Code AnalysisHard
Outbox without proper relay
system-designoutboxdistributed-transactions - Code AnalysisIntermediate
Fire-and-forget event loss
system-designmessagingoutbox - Code AnalysisIntermediate
Outbox relay skipped without ordering
outboxcdcordering - Code AnalysisIntermediate
Outbox pattern race condition
outboxexactly-oncerelay - Code AnalysisBeginner
Transactional Outbox Pattern for Payments
outboxpaymentsevents - Code AnalysisBeginner
Dual Write Ledger and Event Bug
outboxdual-writeevents - Multiple ChoiceHard
Outbox pattern
architectureedaoutbox - Code AnalysisHard
Dual-write inconsistency
architectureedaoutbox - Code AnalysisHard
Outbox vs CDC
outboxcdcdual-write - Code AnalysisIntermediate
Missing transactional outbox
outboxreliabilitycode-analysis
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