Prove your React skills
Almost every frontend CV lists React, so the word alone tells a reader very little. Lemma builds your React record from live sessions, adaptive assessments and the code you have actually shipped.
Preparing for an interview? React interview questions, junior to senior
What React competence looks like
A competent React developer decides where state lives before writing a component. They lift state only as far as it needs to go, reach for context sparingly, and can explain why a component re-rendered. When a list stutters, they check keys, memoisation and effect dependencies before blaming the library.
In practice that also means knowing the boundary between server and client components, using Suspense for loading states instead of scattered spinners, and writing custom hooks that hide messy logic behind a clean interface. They keep effects for synchronising with the outside world, not for deriving data that could be computed during render.
Component architecture review in a live session
60 min · Learning · with Arjun S.
Arjun S. rated the session
Practitioner · after the call
Clear reasoning on component architecture. Talked through trade-offs first.
Component architecture
Splitting UI into composable pieces, choosing props over context, and keeping components small enough to test.
Hooks and effects
Correct dependency arrays, cleanup functions, and knowing when an effect is not needed at all.
State management
Local state, reducers, context and external stores, chosen by how widely the data is shared.
Rendering performance
Diagnosing unnecessary re-renders with the profiler, stable keys, memoisation and splitting heavy subtrees.
Server and client components
Deciding what renders on the server, what ships to the browser, and how data crosses the boundary.
Suspense and data loading
Loading and error boundaries, streaming, and avoiding request waterfalls in nested components.
What counts as evidence of React skills?
Listing React on a profile proves nothing on its own. What counts is a component you shipped, a session where someone watched you debug one, or a test you passed. These are the records Lemma can hold for your React skill, and where each one comes from. See the evidence methodology for how each source is weighed.
React
Felix B. · SCI recomputed 9 Oct
Evidence · 4 entries
- Rated 5.0
Component architecture review in a live session
Live session · 9 Oct
- Level 7.2
Adaptive assessment on hooks and rendering
Adaptive assessment · 2 Oct
- Verified
A React repository connected through GitHub
GitHub connector · 24 Sep
- Verified
A deployed React app via Vercel
Vercel connector · 11 Sep
Component architecture review in a live session
You build or refactor a component with a practitioner watching. They see how you split responsibilities, name props and handle state, then rate the session. That rating becomes React evidence.
Adaptive assessment on hooks and rendering
Scenario questions test effect timing, stale closures and re-render causes. A component re-renders on every keystroke: you pick the change that fixes it from the options.
A React repository connected through GitHub
Link a repository or a specific commit you wrote. Lemma checks the code exists and that your account has access, then re-checks it so the proof stays current.
A deployed React app via Vercel
Connect a Vercel deployment of an app you built. It shows the work runs in production, not only on your laptop.
How is a React skills test run on Lemma?
The React test is adaptive: 15 to 25 questions, each picked from how you answered the last, built around real interface bugs rather than trivia. Its result joins your live sessions and linked repositories or deployments in your React SCI, which also weighs how recent the evidence is.
A search input re-renders the whole results list on every keystroke. Which change fixes it?
- AWrap every child in React.memo
- BKeep the query local and pass a deferred value
- CAdd the list to the useEffect deps
- DCache the results in a useRef
Work through components live
Book a session with a React practitioner and refactor a real component together. Expect questions about why state sits where it does and what triggers each render. Teaching React to someone else counts for more than learning it.
Take the adaptive React assessment
Questions get harder as you answer correctly, and harder ones count for more. Expect realistic scenarios about effects, memoisation and server components, each with a time limit and no going back.
Attach what you have shipped
Connect GitHub or Vercel so your React work sits next to your session and assessment record. Keep practising, because evidence goes stale and your score reflects recent work.
React skills: common questions
How do I prove I know React without a computer science degree?
What should a React portfolio include for a frontend job?
Is a React certification worth it for getting hired?
What React topics come up in technical interviews?
Skills related to React
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Evidence for GraphQL
Start your React evidence record.
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