Next.js
/Intermediate
Code Splitting
Definition
The automated process where Next.js breaks your massive application into hundreds of tiny JavaScript files, ensuring the user only downloads the code necessary for the exact page they are currently viewing.
Explain Like I'm New
If your application has 50 pages, you don't want the user downloading the code for the 'Settings' page when they are just looking at the 'Homepage'. Next.js automatically 'splits' the code. When you visit `/home`, you only download the `home.js` chunk.
Real World Example
An e-commerce site where the heavy JavaScript required to process a Credit Card payment is isolated strictly to the `/checkout` route, keeping the main catalog fast.
Common Use Cases
- •Reducing Time to Interactive (TTI)
- •Scaling massive applications
Terminal Output
bash / terminal
/*
You do absolutely nothing. Next.js handles this automatically!
app/
├── page.tsx <-- Next.js creates 'chunk-home.js'
└── dashboard/
└── page.tsx <-- Next.js creates 'chunk-dashboard.js'
When a user visits /, they ONLY download 'chunk-home.js'.
When they click a <Link> to go to /dashboard, Next.js quickly
fetches 'chunk-dashboard.js' in the background.
*/
Interview Questions
basic
- Do you have to write special configuration code to enable route-based code splitting in Next.js?
intermediate
- How do Server Components take Code Splitting to the absolute extreme?