A newer generation of bundlers, mostly written in Go or Rust, often works inside the tools you use. You meet them directly when you publish a library, migrate a large webpack 3,824 app or adopt a framework that chose one.
| Tool | Language | Latest (Sept 2026) | Best known for | Found in |
|---|---|---|---|---|
| esbuild 126 | Go | 0.28 | Very fast transforms and simple bundles | Angular 42,088 CLI, many tools |
| Rollup 141,981 | JavaScript | 4.63 | Clean ES module output for libraries | Vite 7 25,978 and earlier |
| Rolldown 181,166 | Rust | 1.2 | Rollup-compatible API at native speed | Vite 8 |
| Rspack | Rust | 2.2 | Drop-in replacement for webpack | Rsbuild, Modern.js |
| Turbopack 10,514 | Rust | ships with Next.js 10,514 | Incremental, cached bundling | Next.js 16 (default) |
esbuild bundles, minifies and strips TypeScript types in a single Go binary. It does not type-check (run tsc --noEmit alongside it) and is most often used inside other tools: the Angular CLI's application builder, the default since Angular 17, bundles with esbuild and serves with Vite.
Rollup, first published in 2015, was designed around ES modules from the start. Its plugin API (hooks such as resolveId, load and transform) became the standard that Vite adopted, and it remains a solid choice for publishing libraries. Rolldown, from the VoidZero team behind Vite, reached 1.0 on May 7, 2026: it accepts Rollup plugins and options, is reported as 10 to 30 times faster than Rollup, and uses the Oxc 616,256 parser and minifier.
Rspack was created at ByteDance, where webpack builds of large monoliths took 10 to 30 minutes. It implements the webpack configuration format and loader API in Rust, and its documentation reports that more than 85% of the 50 most-downloaded webpack plugins work or have alternatives. Rspack 2.0 arrived on April 22, 2026. Porting the webpack project of Webpack took a renamed config file and two edits (rspack.HtmlRspackPlugin and the built-in type: 'css/auto' rule instead of the CSS loaders), and the production build finished in 38 ms.
Turbopack, from Vercel 3,061 , is not a general-purpose CLI: it is built into Next.js and has been its default bundler since Next.js 16 (October 2025). Unlike Vite it does bundle in development, but lazily, and it caches results down to individual functions on disk between runs. It supports webpack loaders but not webpack plugins; next build --webpack switches back.