# Next.js Skills Test and Verified Next.js Score > A Next.js skills test on the App Router, caching and rendering, plus live code reviews and connected Vercel deployments. See what proves Next.js skills. Source: https://getlemma.io/skills/nextjs Next.js work is mostly decisions: what renders where, what gets cached and for how long. Lemma records those decisions through live sessions, adaptive assessments and the apps you have deployed. How Next.js is assessed ## What Next.js competence looks like A capable Next.js developer picks a rendering strategy per route on purpose. They know when a page should be static, when it needs request-time data, and how caching and revalidation affect what a visitor actually sees. When stale data shows up in production, they know which cache to look at. They structure the App Router cleanly with layouts, loading and error files, keep client components small, and move data fetching to the server. They also care about the parts users feel: image and font optimisation, metadata for search, and middleware that stays fast because it runs on every request. ### App Router structure Layouts, nested routes, route groups, and loading and error boundaries organised around the user's journey. ### Rendering strategies Static generation, dynamic rendering and streaming chosen per route based on the data each one needs. ### Caching and revalidation Request memoisation, data cache, revalidation by time or tag, and debugging stale content. ### Server actions and forms Mutations on the server, progressive enhancement, validation and safe handling of user input. ### Metadata and SEO Per-page metadata, canonical URLs, structured data and generated social images. ### Performance and assets Image and font optimisation, bundle size, and keeping client JavaScript to what the page needs. ## What counts as evidence of Next.js skills? Listing Next.js 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 Next.js skill, and where each one comes from. See the [evidence methodology](https://getlemma.io/methodology#evidence-types) for how each source is weighed. [Vercel connector](https://getlemma.io/product/passport) ### A deployed Next.js app on Vercel Connect a Vercel deployment of a Next.js project you built. Lemma checks that the deployment exists and that your account has access, then re-checks it over time. [GitHub connector](https://getlemma.io/product/passport) ### Your Next.js repository on GitHub Link the repository behind the app, or the commit where you moved a route to server rendering. It shows how your routes, layouts and data fetching are organised. [Live session](https://getlemma.io/product/sessions) ### Route architecture walkthrough in a live session Talk a practitioner through your rendering and caching choices, or build a route together. Their rating records how clearly you reason about the server and client boundary. [Adaptive assessment](https://getlemma.io/product/assessments) ### Adaptive assessment on rendering and caching Scenario questions ask which strategy fits a page and why content went stale. Harder rounds show route code and ask you to pick the real cause. ## How is a Next.js skills test run on Lemma? The Next.js 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 Next.js SCI, which also weighs how recent the evidence is. [How the SCI score is calculated](https://getlemma.io/product/sci)[How adaptive skills assessments work](https://getlemma.io/product/assessments)[Practise Next.js in live skill swap sessions](https://getlemma.io/product/sessions)[Which evidence types count](https://getlemma.io/methodology#evidence-types)[What your Skills Passport shows](https://getlemma.io/product/passport) 1. ### Walk through a real app In a live session, show a Next.js project or build a route with a practitioner. Expect questions about why a page is static or dynamic, where data is fetched, and how revalidation works. 2. ### Answer adaptive scenarios The Next.js assessment adjusts to your answers. Realistic scenarios cover rendering choices, caching, server actions and middleware. Harder questions count for more, and you can't go back. 3. ### Connect the deployment Link the Vercel deployment and GitHub repository so your live sessions and assessment sit next to working software. Recent evidence counts for more, so keep shipping. ## Next.js skills: common questions ### How do I prove I can build production apps with Next.js? Connect a live Vercel deployment and its GitHub repository, then walk a practitioner through your rendering and caching choices in a session. Add an adaptive assessment result and you have three kinds of evidence that point at the same skill. ### What Next.js questions come up in frontend interviews? Common ones cover static versus dynamic rendering, how caching and revalidation work, the server and client component boundary, server actions and metadata for search. The Next.js assessment on Lemma tests the same areas with realistic scenarios. ### Do I need to know React well before proving Next.js? Yes, mostly. Next.js builds on React, so weak component and state skills show up quickly in a session. Lemma tracks React and Next.js as separate skills, so you can build evidence for both and each score stays honest. ### Can a side project count as Next.js evidence? Yes. A side project you deployed is real evidence of how you build. Connect it through Vercel or GitHub, and pair it with a live session where you explain the decisions behind it. A practitioner's rating adds the context the code alone cannot show. ## Skills related to Next.js [Browse the skills directory](https://getlemma.io/skills) [### React Show how you structure components, manage state and keep renders fast, with evidence behind it. Evidence for React](https://getlemma.io/skills/react)[### TypeScript Show that your types catch real bugs instead of just silencing the compiler. Evidence for TypeScript](https://getlemma.io/skills/typescript)[### Node.js Evidence of how you build and debug Node.js services, from the event loop to production errors. Evidence for Node.js](https://getlemma.io/skills/nodejs)[### JavaScript Evidence that you understand how JavaScript runs, not just how to write its syntax. Evidence for JavaScript](https://getlemma.io/skills/javascript) ![Painting of an olive grove in soft sunlight with hills beyond](https://cdn.sanity.io/images/islu4peo/production/613eb3f93566423c9adf45246f2cf1a61437c04c-1680x1120.jpg?w=1080&fm=webp&q=68&fit=max) ## Start your Next.js evidence record. Lemma is in early access. Request an invite and we will email you when your place is ready.