2,140
Learners
verifying this skill
4,821
Sessions
completed to date
71
Avg SCI
across all levels
4
Tiers
claimed → peer-endorsed
Book a peer session and build or review a React component live
hooks, state, and all.
Your session partner rates your component architecture, perf
Your session partner rates your component architecture, performance awareness, and idiomatic usage. Evidence is committed to your passport.
Repeat sessions compound your SCI score across Practice, Pro
Repeat sessions compound your SCI score across Practice, Proof, and Reliability components.
React — facts worth knowing.
React was originally built for Facebook's News Feed in 2011 and open-sourced in 2013 – now it powers over 10 million websites.
Did you know?
The React team introduced hooks in v16.8 (2019) specifically to make it easier to share stateful logic without changing component hierarchy.
Did you know?
Server Components, introduced in React 18, shift rendering entirely to the server for zero-JS payload – a paradigm shift that most 'React developers' haven't internalized yet.
Did you know?
Why React matters.
React is a JavaScript library for building component-based user interfaces with declarative rendering. It powers everything from simple widgets to large-scale single-page apps. On Lemma, React sessions test your command of hooks, composition patterns, state management, and the concurrent rendering model.
React is the most-requested frontend skill in engineering job postings globally. Verified React proficiency shortens hiring cycles and commands measurably higher compensation. SCI-backed proof separates practitioners from people who followed a tutorial once.
2,140 people are learning this on Lemma
4,821 peer sessions completed
Avg SCI of 71 — tier 3 practitioners
avg SCI on Lemma
React practitioners
Related skills
React verification — common questions
Book a peer session where you build or review React components in real time. Your partner evaluates your hooks usage, component architecture, state management approach, and your instincts around re-rendering. Evidence from each session is permanently logged to your Skills Passport.
Your React SCI is computed from five components: Practice (session frequency), Proof (rated evidence quality), Reliability (consistency across peers), Freshness (recency of sessions), and Integrity (no disputed results). It reflects demonstrated ability, not self-reported claims.
Sessions typically surface hooks (useState, useEffect, useCallback, useMemo), component composition and reuse, controlled vs. uncontrolled patterns, and performance intuition. Advanced sessions add concurrent features, Suspense, and server vs. client component boundaries.
Bootcamp certificates prove attendance. Lemma verification proves demonstrated ability through live peer sessions – the evidence includes what you built, how you reasoned through trade-offs, and how your peer rated your work. Employers can inspect the evidence directly.
No. You can verify React with JavaScript. If you also write React with TypeScript, your sessions will naturally demonstrate that combination and add type-system evidence to your passport alongside your React SCI.
Start verifying your React skills.
Join the waitlist. Your first peer session is free.