Next.js

Next.js is an open-source framework for building web applications based on the React library, developed by Vercel. It extends React with capabilities the library does not provide on its own: server-side rendering, static site generation, built-in routing and a range of performance optimizations. This lets developers create fast, SEO-friendly applications without manually assembling the entire infrastructure.

How Next.js works

Next.js's key strength is rendering flexibility. The framework can produce a page in several ways: SSR (Server-Side Rendering) generates HTML on the server for each request; SSG (Static Site Generation) builds pages once at compile time and serves them as static files; and ISR refreshes static pages in the background. This solves a core limitation of browser-only SPAs, which can be harder to index and slower to display their first content.

Next.js bases routing on the file structure — a new file in the appropriate directory automatically becomes a new application route. Newer versions introduced the App Router with server components, which shift part of the logic to the server and reduce the amount of code shipped to the browser. The framework runs in the Node.js environment.

Practical application

Next.js fits anywhere interactivity and strong search visibility both matter: online stores, content portals, blogs, dashboards and marketing sites. In static generation mode it aligns well with the JAMstack architecture.

Deployment depends on the mode. An SSR application needs a Node.js environment — the most convenient place to run it is a VPS or a platform with a Node runtime, where the app process stays up continuously. A fully static build can be exported and served from any hosting or CDN, which keeps the infrastructure minimal and inexpensive.