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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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54 challenges matching your filters
Clear topic filter- Multiple ChoiceBeginner
SRP: finding the second reason to change
architecturesolidsrp - Multiple ChoiceBeginner
LSP and equals/hashCode contract
architecturesolidlsp - Multiple ChoiceBeginner
Strategy vs if/else
architecturedesign-patternsstrategy - Multiple ChoiceBeginner
Factory Method vs Abstract Factory
architecturedesign-patternsfactory - Multiple ChoiceBeginner
Adapter vs Facade
architecturedesign-patternsadapterfacade - Multiple ChoiceBeginner
Command pattern: undo
architecturedesign-patternscommand - Multiple ChoiceBeginner
Strangler Fig core idea
architecturemigrationstrangler-fig - Multiple ChoiceBeginner
Sidecar vs Ambassador
architecturedesign-patternssidecarambassador - Multiple ChoiceBeginner
Bounded context definition
architecturedddbounded-context - Multiple ChoiceBeginner
Entity vs Value Object
architecturedddvalue-object - Multiple ChoiceBeginner
Ports and adapters essence
architecturehexagonalports-adapters - Multiple ChoiceBeginner
Anemic vs rich domain model
architecturedddanemic-model - Multiple ChoiceBeginner
Layered architecture direction
architecturelayering - Multiple ChoiceBeginner
Modular monolith benefit
architecturemonolithmodularity - Multiple ChoiceBeginner
When microservices hurt
architecturemicroservicestrade-offs - Multiple ChoiceBeginner
Cost of Change Meaning
cost-of-changeeconomicsarchitecture - Multiple ChoiceBeginner
Technical Debt Definition
technical-debtarchitecturetradeoffs - Multiple ChoiceBeginner
YAGNI at Architecture Level
yagnisimplicityarchitecture - Multiple ChoiceBeginner
API versioning: additive change
architectureapiversioningbackward-compatibility - Multiple ChoiceBeginner
Test pyramid rationale
architecturetestingtest-pyramid - Multiple ChoiceBeginner
Stub vs mock vs fake
architecturetestingtest-doubles - Multiple ChoiceBeginner
Dependency injection benefit
architecturetestingdi - Multiple ChoiceBeginner
ADRs purpose
architectureadrdocumentation - Multiple ChoiceBeginner
Cyclic dependencies harm
architecturemodularitydependencies - Multiple ChoiceBeginner
Package cohesion: CCP
architecturemodularitycohesion - Multiple ChoiceBeginner
Facade reduces coupling
architecturedesign-patternsfacade - Multiple ChoiceBeginner
Cross-cutting logging
architecturecross-cuttinglogging - Multiple ChoiceBeginner
Config as external concern
architectureconfigurationtwelve-factor - Multiple ChoiceBeginner
Composition over inheritance
architectureoopcomposition - Multiple ChoiceBeginner
Anti-corruption in practice
architecturedddacl - Multiple ChoiceBeginner
Port naming by role
architecturehexagonalnaming - Code AnalysisBeginner
Anemic model allows invalid state
architecturedddanemic-model - Code AnalysisBeginner
SRP: god class
architecturesolidsrp - Code AnalysisBeginner
LSP: equals/hashCode mismatch
architecturesolidlsp - Code AnalysisBeginner
Coupling metric read
architecturemetricscoupling - Code AnalysisBeginner
Command with undo
architecturedesign-patternscommand - Code AnalysisBeginner
Feature flag stale branch
architecturefeature-flagstechnical-debt - Code AnalysisBeginner
Command/query separation violation
architecturecqrsprinciples - Code AnalysisBeginner
ISP in a module interface
architecturesolidisp - Code AnalysisBeginner
CQRS lag breaks read-your-writes
architecturecqrseventual-consistency - Code AnalysisBeginner
Anemic model with validation elsewhere
architecturedddanemic-model - Code AnalysisBeginner
Dependency inversion missing in service
architecturesoliddip - Code AnalysisBeginner
Choreography observability gap
architectureedasaga - Code AnalysisBeginner
Shared module creates cycle at package level
architecturemodularitydependencies - Code AnalysisBeginner
Bulkhead absence cascades
architectureresiliencebulkhead - Code AnalysisBeginner
Test double misuse
architecturetestingtest-doubles - Code AnalysisBeginner
Branch by abstraction setup
architecturerefactoringbranch-by-abstraction - Code AnalysisBeginner
Value object mutability bug
architecturedddvalue-object - Code AnalysisBeginner
Modular monolith boundary enforcement
architecturemodularitymonolith - Code AnalysisBeginner
Query side should not be reused for writes
architecturecqrsseparation - Code AnalysisBeginner
Anemic DTO vs domain object
architecturedddanemic-model - Code AnalysisBeginner
Strangler deletion debt
architecturemigrationstrangler-fig - Code AnalysisBeginner
Dependency injection container misuse
architecturedicoupling - Code AnalysisBeginner
Cyclic dependency via event handler
architecturemodularityeda
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