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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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702 challenges matching your filters
- Code AnalysisIntermediate
Eventual consistency bug after write
architecturecqrseventual-consistency - Code AnalysisIntermediate
Decorator vs subclass explosion
architecturedesign-patternsdecorator - Code AnalysisIntermediate
Circuit breaker covers wrong scope
architectureresiliencecircuit-breaker - Code AnalysisIntermediate
Fitness function for layering
architecturefitness-functionshexagonal - Code AnalysisIntermediate
Repository leaking persistence
architecturedesign-patternsrepository - Code AnalysisIntermediate
Aggregate reference by object
architecturedddaggregate - Code AnalysisIntermediate
Strangler with broken routing
architecturemigrationstrangler-fig - Code AnalysisIntermediate
Wrong abstraction via forced hierarchy
architectureover-abstractionlsp - Code AnalysisIntermediate
Ambassador vs Sidecar use
architecturedesign-patternssidecarambassador - Code AnalysisIntermediate
Adapter vs Facade distinction by code
architecturedesign-patternsadapter - Code AnalysisIntermediate
Bounded context language clash
architecturedddbounded-context - Code AnalysisIntermediate
Backpressure ignored
architectureresiliencebackpressure - Code AnalysisIntermediate
Event sourcing projection replay bug
architectureevent-sourcingprojections - Code AnalysisIntermediate
LSP: widening (not narrowing) can also break
architecturesolidlsp - Code AnalysisIntermediate
Contract regression: additive vs breaking
architectureapiversioningbackward-compatibility - Code AnalysisIntermediate
Orchestration single point
architecturesagaresilience - Code AnalysisIntermediate
Abstractness/instability zone check
architecturemetricscoupling - Code AnalysisIntermediate
Test seam for legacy code
architecturetestingseams - Code AnalysisIntermediate
Analyze: LSP behavioral subtyping break
lspsolidsubtyping - Code AnalysisIntermediate
Analyze: DIP ownership direction
diprepositoryhexagonal - Code AnalysisIntermediate
Analyze: SRP multiple reasons to change
srpsolidcohesion - 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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