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Follow a study plan from start to finish, or pick one skill and drill it until the tests pass on the first run.

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Sample plans · progress shows 0% until you solve their problems

React Fundamentals

State, lists and events by hand, no libraries.

Start with Todo List

React UIBeginner12 problems

0 / 12 solved

Showing 5 of 12. Locked steps open when their tests ship.

More React UI plans

Accessible Components
Keyboard support, focus and ARIA that tests can prove.
React UIIntermediate9 problems
0%
Async UI
Debounce, cancellation, loading and error states.
React UIIntermediate8 problems
0%
Forms & Validation
Controlled inputs, multi-step flows, error messages.
React UIBeginner10 problems
0%

Interview 75

DSA track arrives later

The classic arrays, strings and graphs set.

DSAIntermediate75 problems

Dynamic Programming

DSA track arrives later

From memoised recursion to tabulation.

DSAAdvanced24 problems

Skills

Problem counts by skill across the library. The bar shows the easy, medium and hard mix.

React UI

Data structures & algorithms

Prepare for interviews

Front-end interviews ask you to build a working component in under an hour. Practise the same thing: no AI, no copy-paste, just you, the editor and the tests.

Practise React UI problems Open the problem library