Published at: May 12, 2022
With the release of Next.js 13, the React framework has introduced several exciting new features that significantly improve the developer experience, performance, and scalability of applications. In this post, we’ll dive into what has changed between Next.js 12 and Next.js 13, and how you can migrate your app to take advantage of these powerful new features.
1. Introduction to Next.js 13
Next.js 13 introduces several major updates, including:
- The App Router
- React Server Components (RSCs)
- Edge Functions
These new features revolutionize the way we build and deploy Next.js applications. Let’s break them down.
2. New Features in Next.js 13
1. The App Router
Next.js 13 introduces a new routing system called the App Router. This is designed to streamline the way you handle server-side rendering (SSR), static site generation (SSG), and dynamic routes.
The App Router moves routing into the app/ directory, which simplifies the organization of your project. You no longer need to worry about pages/
for routing.
Here’s what’s new with the App Router:
- File-based routing—The routing mechanism in Next.js 13 is based on the new
app/
directory (instead of thepages/
directory). - Layouts and nested routing—You can now define layouts and components that can be reused across multiple routes.
- React Suspense integration—App Router allows you to use React Suspense for handling data fetching and asynchronous operations seamlessly.
2. React Server Components (RSCs)
React Server Components are one of the most exciting features in Next.js 13.
React Server Components allow certain components to render on the server and only send HTML (not JavaScript) to the client. This reduces JavaScript bundle size and improves performance by minimizing the client’s workload.
Some key benefits of Server Components:
- Smaller client-side JavaScript
- Reduced time to interactive (TTI)
- No client-side state management for certain components
3. Edge Functions
Edge Functions are another powerful feature in Next.js 13. Edge Functions allow you to run serverless functions closer to the user, minimizing latency and providing near-instant responses.
With Edge Functions, your app can scale globally with faster response times, and you can deploy your app at the edge for performance optimization.
3. Key Differences Between Next.js 12 and Next.js 13
1. App Directory vs. Pages Directory
In Next.js 12, the routing system relied on the pages/
directory. However, in Next.js 13, you should use the app/
directory for better performance, more flexible layouts, and an improved experience with React Suspense.
Feature | Next.js 12 | Next.js 13 |
---|---|---|
Routing | pages/ directory | app/ directory |
Data Fetching | getStaticProps , getServerSideProps | React Suspense and Server Components |
React Server Components | Not supported | Fully supported |
2. React Server Components
While React Server Components are not supported in Next.js 12, they are fully supported in Next.js 13, which means you can now leverage them for rendering components on the server.
Feature | Next.js 12 | Next.js 13 |
---|---|---|
React Server Components | Not available | Fully integrated |
3. Edge Functions
Edge Functions are new in Next.js 13. They allow you to run functions in distributed locations close to the user, providing faster execution times and improved performance. In Next.js 12, edge functions were not natively supported.
4. How to Migrate from Next.js 12 to Next.js 13
Migrating from Next.js 12 to Next.js 13 is straightforward but requires some careful planning. Here’s how to make the transition:
Step 1: Update Dependencies
First, update your project dependencies to use Next.js 13. You can do this via the following command:
npm install next@latest react@latest react-dom@latest
Step 2: Migrate to the App Directory
In Next.js 13, you should start using the app/
directory for routing instead of the pages/
directory.
- Move your existing pages from
pages/
toapp/
following the new file structure. - Create a
page.js
file for each route you want to define. - Use React Suspense and layouts in your routes to improve performance.
Step 3: Use React Server Components
Once you’ve moved to the app/
directory, you can start using React Server Components.
- To create Server Components, simply add an
.server.js
file for components that need to run on the server. - Server components will never send JavaScript to the browser, only the HTML.
Step 4: Migrate to Edge Functions
If your app requires global scaling, consider migrating some of your functions to Edge Functions.
- Set up edge deployment via Vercel, which makes it easy to deploy and run your Next.js app with Edge Functions.
5. Final Thoughts
Next.js 13 brings significant improvements to how we build React applications. With the introduction of the App Router, React Server Components, and Edge Functions, your applications can be faster, more scalable, and easier to maintain.
If you’re currently using Next.js 12, upgrading to Next.js 13 is definitely worth considering for the performance gains and the new routing system.
Ready to start building with Next.js 13? Let us know how the migration goes and any tips you have for the community!