ExamopotamiaWhy test React skills before the interview?
React is on a huge number of front-end CVs, and tutorials make it look simple. The gaps show up in real projects: mutated state that never re-renders, effects that run in loops, lists that swap data between rows. A short, timed React test checks the mental model behind the code, so your engineers can spend interviews on design and experience instead of the basics.
What this template covers
- Components and data flow: props, controlled inputs and lifting state.
- State updates: immutable updates and the functional form of
setState. - Effects: dependency arrays, cleanup functions and stale requests after fast changes.
- Lists: what keys do and why index keys can cause bugs.
- Hooks: the rules of hooks and when
useMemois worth using.
How to run it well
Twelve questions in about 15 minutes works for a screen. Several items show a short snippet, so give people time to read. A pass mark of 65% suits junior roles; for mid and senior developers, aim for 75% and add your own questions on state management, data fetching libraries or server rendering.
Turn on question and option shuffling, and use a random subset if many people apply. Pay particular attention to the batching question and the stale request scenario. They separate developers who have debugged real React apps from those who have only followed tutorials.
Who this test is for
Use it for React and front-end developers, full-stack developers whose work includes a React front end, React Native developers checking the shared fundamentals, and graduates of bootcamps that teach React. Agencies can use it to vet contractors before a client project. Back-end developers who are expected to work across the stack can take it too, which shows whether they can handle front-end tickets on their own. The questions avoid framework add-ons, so they are fair for people who used different routers or state libraries.
Make it yours
Add questions on the rest of your stack: TypeScript types for props, your router, your state library, Next.js or your testing tools. A snippet from your own codebase with a planted bug makes a good hard question. The AI generator can draft more hook questions for you to review, and answers are checked on the server so the key never appears in the page. Keep snippets to a few lines so candidates spend their time thinking, not scrolling.