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Official6 problems · ~4.5h total
Zero to Hero: React
Go from React fundamentals to interview-ready. A difficulty-ramped set of multi-concept React problems — controlled components, derived state, effects and cleanup, memoization and re-render control, controlled vs uncontrolled inputs, and keys/reconciliation — each graded by black-box Playwright tests over the real DOM. Built to help you pass the React front-end interview.
0/6 solved0%
Warm-up — Fundamentals
Core — Hooks & Performance
Stop the Re-renders — useMemo, useCallback, React.memo
Debugging · 45 min · react-hooks, performance-optimization
Challenge — Advanced Patterns
Controlled vs Uncontrolled — Tame the Form + Focus
Debugging · 45 min · react-hooks, state management, focus management
Keys & Reconciliation — No State Bleed on Reorder
Debugging · 45 min · react-hooks, state-management