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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447 challenges matching your filters
Clear topic filter- Multiple ChoiceIntermediate
useReducer
frontendintermediate - Multiple ChoiceIntermediate
Context API
frontendintermediate - Multiple ChoiceIntermediate
Redux
frontendintermediate - Multiple ChoiceIntermediate
Zustand
frontendintermediate - Multiple ChoiceHard
Signals
frontendhard - Multiple ChoiceHard
Jotai/Recoil
frontendhard - Multiple ChoiceIntermediate
MobX
frontendintermediate - Multiple ChoiceHard
XState
frontendhard - Multiple ChoiceIntermediate
TanStack Query
frontendintermediate - Multiple ChoiceIntermediate
URL state
frontendintermediate - Multiple ChoiceIntermediate
Lifting state up
frontendintermediate - Multiple ChoiceIntermediate
Immutable updates
frontendintermediate - Multiple ChoiceHard
Optimistic updates
frontendhard - Multiple ChoiceHard
State normalization
frontendhard - Multiple ChoiceIntermediate
Jest
frontendintermediate - Multiple ChoiceIntermediate
React Testing Library
frontendintermediate - Multiple ChoiceIntermediate
Cypress
frontendintermediate - Multiple ChoiceIntermediate
Unit tests
frontendintermediate - Multiple ChoiceIntermediate
Integration tests
frontendintermediate - Multiple ChoiceIntermediate
E2E tests
frontendintermediate - Multiple ChoiceIntermediate
Mocking
frontendintermediate - Multiple ChoiceIntermediate
Snapshot testing
frontendintermediate - Multiple ChoiceIntermediate
Test coverage
frontendintermediate - Multiple ChoiceIntermediate
Accessibility testing
frontendintermediate - Multiple ChoiceHard
Visual regression
frontendhard - Multiple ChoiceHard
MSW
frontendhard - Multiple ChoiceBeginner
Backend for Frontend (BFF)
bffapi-gatewayfrontend
Practice now, dominate the arena
Every challenge here is drawn from the live Code Royale pool. Review a question, then head to the arena to answer under pressure against a real opponent — 3-minute matches, Elo ranking, and badge tiers on the line.