It is also a bundler and minifier and dead code tree-shaker. It combines all your modules into one file (or a few) for production. In development it doesn’t do the bundling part (for now — with Rolldown[0] replacing Rollup[1] in the future, bundling will be fast enough to do the same in dev and prod).

It also serves as an integration point for other kinds of tooling that involves processing or generating code. For example, the latest versions of React Router[2] (which now integrates Remix's features) and Tailwind[3] are designed primarily to be integrated into projects as Vite plugins.

[0]: https://rolldown.rs/

[1]: https://rollupjs.org/

[2]: https://reactrouter.com/home#react-router-as-a-framework

[3]: https://tailwindcss.com/blog/tailwindcss-v4#first-party-vite...