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Coding Challenges
5,893 curated questions across every arena — browse by topic, then jump into a live 2-minute battle to put them to the test.
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2,721 challenges matching your filters
- Code AnalysisIntermediate
Transactional Boundary Violation
transactionsconsistencyaggregates - Code AnalysisIntermediate
Ports and Adapters Testing
hexagonalports-adapterstestability - Code AnalysisIntermediate
Enforcing Boundaries with ArchUnit
archunitboundariesfitness-functions - Code AnalysisIntermediate
Event Versioning / Upcasting
event-sourcingupcastingversioning - Code AnalysisIntermediate
Authorization Model Fit
authorizationrebacabac - Code AnalysisIntermediate
Missing transactional outbox
outboxreliabilitycode-analysis - Code AnalysisIntermediate
Sync engine conflict handling
sync-engineconflict-resolutioncode-analysis - Code AnalysisIntermediate
DIP violation via direct SDK import
dipports-and-adapterscode-analysis - Code AnalysisIntermediate
Fat interface / ISP violation
ispsolidcode-analysis - Code AnalysisIntermediate
Composition over inheritance refactor
compositioninheritancecode-analysis - Code AnalysisIntermediate
Template method wrong fit
template-methodstrategycode-analysis - Code AnalysisIntermediate
Strategy vs state selection
statestrategycode-analysis - Code AnalysisIntermediate
Visitor for business rules
visitorpatternscode-analysis - Code AnalysisIntermediate
Durable execution vs retries
durable-executionworkflow-enginecode-analysis - Code AnalysisIntermediate
Data contract for analytics eventing
data-contractseventingcode-analysis - Code AnalysisIntermediate
Which Evolution Strategy Fits
expand-contractschema-evolutioncode-analysis - Code AnalysisIntermediate
Which Consistency Flaw
sagacompensationcode-analysis - Code AnalysisIntermediate
Which Backpressure Gap
backpressureoverloadcode-analysis - Code AnalysisIntermediate
Which Event Versioning Issue
event-versioningcompatibilitycode-analysis - Code AnalysisIntermediate
Which Orchestration vs Choreography
choreographyorchestrationobservabilitycode-analysis - Code AnalysisIntermediate
Which Fallback Design Gap
graceful-degradationfallbackcode-analysis
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