What is nextjs?

Next.js is a free, open‑source framework built on top of React that helps developers create fast, server‑rendered web applications. Think of it as a toolbox that adds extra features-like automatic page routing, built‑in CSS support, and easy data fetching-to the basic React library, making it simpler to build modern websites.

Let's break it down

  • React base: Next.js uses React for building UI components, so you write JSX just like in a regular React app.
  • Pages folder: Any file you put in the “pages” directory automatically becomes a route (e.g., pages/about.js → /about).
  • Server‑Side Rendering (SSR): Pages can be rendered on the server before they reach the browser, improving load speed and SEO.
  • Static Site Generation (SSG): You can pre‑build pages at build time, turning them into static HTML files that load instantly.
  • API routes: You can create backend endpoints inside the same project (e.g., pages/api/users.js).
  • Built‑in CSS/Images: Next.js handles CSS modules, global styles, and image optimization without extra configuration.

Why does it matter?

  • Performance: SSR and SSG make pages load faster, which keeps visitors happy and helps search engines rank your site higher.
  • Developer experience: Automatic routing, hot‑reloading, and zero‑config setup let you focus on building features instead of wiring infrastructure.
  • Scalability: You can start with a simple static site and later add server‑side features without moving to a new framework.
  • SEO friendliness: Because content can be rendered on the server, search bots can read it easily, unlike pure client‑side React apps.

Where is it used?

  • E‑commerce sites (e.g., Shopify storefronts) that need fast load times and SEO.
  • Marketing and landing pages for startups and agencies.
  • Content‑heavy blogs or news portals that benefit from static generation.
  • SaaS dashboards where you want a mix of static UI and dynamic data fetching.
  • Large companies like Netflix, TikTok, and Uber use Next.js for parts of their web platforms.

Good things about it

  • Zero‑config start: Run npx create-next-app and you have a working project instantly.
  • Hybrid rendering: Choose SSR, SSG, or client‑side rendering per page.
  • File‑system routing eliminates the need for a separate router setup.
  • Built‑in API routes let you add backend logic without a separate server.
  • Image and font optimization out of the box improves performance.
  • Strong community and Vercel support (the company behind Next.js) provides frequent updates and excellent documentation.

Not-so-good things

  • Learning curve: Beginners must understand both React and Next.js concepts like SSR, SSG, and data‑fetching methods.
  • Build size: Large projects can produce bigger bundles if not carefully optimized.
  • Serverless limits: API routes run on serverless functions, which may have cold‑start latency or execution time limits.
  • Opinionated structure: The “pages” folder and routing conventions may feel restrictive if you prefer a custom architecture.
  • Version churn: Frequent major releases sometimes require migration work to stay up‑to‑date.