Next.js Mastery: A Comprehensive Guide - Part 4: Rendering Strategies and ISR
Next.js Mastery: A Comprehensive Guide - Part 4: Rendering Strategies and ISR
Introduction
One of the most powerful aspects of Next.js is its ability to choose the rendering strategy that best fits each page in your application. In this part, we will explore the different rendering strategies and the game-changing Incremental Static Regeneration (ISR).
Rendering Strategies
1. Static Site Generation (SSG)
Pages are generated at build time. This is the fastest possible way to serve pages.
- Best for: Blogs, documentation, marketing pages where content doesn’t change often.
2. Server-Side Rendering (SSR)
Pages are generated on the server for every single request.
- Best for: Personalized pages (e.g., user profile), pages with real-time data, search results.
3. Incremental Static Regeneration (ISR)
ISR is a hybrid approach. It allows you to use Static Generation on a per-page basis, without needing to rebuild the entire site. You can update static content after you’ve built your site, in the background, by revalidating the page.
1
2
3
4
5
6
7
8
9
10
11
12
13
// Example of ISR in a page
export async function generateStaticParams() {
const posts = await getPosts();
return posts.map((post) => ({ slug: post.slug }));
}
export default async function Page({ params }) {
const post = await getPost(params.slug);
return <div>{post.title}</div>;
}
// ISR: Revalidate this page at most every 60 seconds
export const revalidate = 60;
Why ISR Matters
ISR provides the speed of static pages with the freshness of dynamic ones. It solves the trade-off between build times (for large sites) and content staleness.
Conclusion
Understanding when to use SSG, SSR, or ISR is crucial for building performant and scalable Next.js applications. ISR in particular is a powerful tool for managing content that needs to stay fresh without the overhead of full site rebuilds.