Train the way you actually interview.

Three surfaces, three kinds of thinking. One asks you to write the code, one asks you to read it, one asks you to see it land on screen. Pick the gap you want to close.

Frontend interview · senior

Ten FAANG-style problems with a coach that pushes back. Sandboxed Web Worker, real test runs, three hints per problem.

10 questions · senior

~215 min total

0 / 10 passed

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Time complexity · drill

Read a snippet, pick its Big-O. The reverse direction of live coding — train your eye on the access patterns that drive runtime.

26 questions · all levels

~39 min total

0 / 26 passed

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Calendar UI · React + CSS

Six calendar views built with JSX and CSS, from a 7-column month grid to a year heatmap. Live iframe with React + Babel, structural assertions, reference solution one keypress away.

6 questions · all levels

~94 min total

0 / 6 passed

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