Next.js Fundamentals

Next.js is a powerful React framework that enables you to build production-ready web applications. Let's explore its core features and best practices.

Server-Side Rendering (SSR)

Next.js provides built-in SSR capabilities:

export async function getServerSideProps(context) {
	const data = await fetchData();
	return {
		props: { data },
	};
}

Static Site Generation (SSG)

Pre-render pages at build time:

export async function getStaticProps() {
	const posts = await getPosts();
	return {
		props: { posts },
		revalidate: 60, // Optional ISR
	};
}

File-Based Routing

Next.js uses a file-system based router:

pages/
  index.js        // -> /
  about.js        // -> /about
  blog/
    [slug].js     // -> /blog/:slug
    index.js      // -> /blog

API Routes

Create API endpoints within your Next.js app:

// pages/api/users.js
export default function handler(req, res) {
	if (req.method === "GET") {
		res.status(200).json({ users: [] });
	}
}

Image Optimization

Use the built-in Image component for optimal performance:

import Image from "next/image";

function MyComponent() {
	return (
		<Image src="/profile.jpg" alt="Profile" width={500} height={300} priority />
	);
}

Data Fetching Patterns

Client-Side Data Fetching

import useSWR from "swr";

function Profile() {
	const { data, error } = useSWR("/api/user", fetcher);

	if (error) return <div>Error loading</div>;
	if (!data) return <div>Loading...</div>;
	return <div>Hello {data.name}!</div>;
}

Performance Optimization

1. Use dynamic imports for code splitting
2. Implement proper caching strategies
3. Optimize images and fonts
4. Leverage Edge Functions for faster response

Best Practices

1. Follow the recommended project structure
2. Use appropriate data fetching methods
3. Implement proper error boundaries
4. Optimize for Core Web Vitals
5. Use TypeScript for better type safety

Deployment

Next.js applications can be easily deployed to various platforms:

• Vercel (Zero configuration)
• AWS
• Google Cloud
• Custom server

Conclusion

Next.js provides a robust framework for building modern web applications with features like SSR, SSG, and automatic image optimization. Understanding these fundamentals will help you create performant and scalable applications.