Beyond the usual quick tips, let's look at both the business case and the technical side of keeping React bundles lean.

Lastly, index.js serves as the starting point for the NodeJS process and ReactDOM.hydrate () is used to flesh out our app with less important auxiliary content after the shell loads.

Now stable in Next.js 13.4, the new App Router builds on React Server Components and React Suspense to improve data fetching, page loading, and the developer experience.