Rslib vs SWC
Rslib
lib.rsbuild.dev
SWC
swc.rsSide by side
| Figure | Rslib | SWC |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| Android | — | Yes |
| API | Yes | Yes |
| Plans published | 1 | 1 |
| Spec score · JavaScript Build Tools | 8.6 (#2) | 8.3 (#4) |
| Community support | The project invites users to chat with the Rstack team and community on Discord. | The site invites users to join GitHub discussions and Discord. |
| Performance | Rslib is powered by Rspack and integrates Rust-based tools including SWC and Lightning CSS. | The site states that SWC is 20x faster than Babel on a single thread and 70x faster on four cores. |
| Purpose | Rslib is an Rsbuild-based tool for developing JavaScript libraries and UI component libraries. | SWC is an extensible Rust-based platform for fast developer tools that can compile and bundle JavaScript and TypeScript. |
Plans
In their own words
Rslib
Rslib is a free, open-source tool for developing JavaScript packages and UI component libraries. Based on Rsbuild and powered by Rspack, it integrates Rust-based tools including SWC and Lightning CSS. It supports bundle and bundleless build modes and outputs ESM, CJS, UMD, Module Federation, and IIFE formats. Framework integrations support component libraries for React, Vue, Svelte, and Solid. Rslib can generate TypeScript declaration files, including isolated declarations, though declaration generation is not enabled by default. Plugin support includes Rsbuild, Rspack, and webpack plugins. Its development integrations include Rstest for testing, Storybook for component development, Rspress for documentation and component previews, and Rsdoctor for build analysis. The quick-start guide lists Node.js, Deno, and Bun as runtime options, while Rslib v1 requires Node.js 20.19+ or 22.12+. It is available for API, Linux, macOS, web, and Windows, and is released under the MIT license.
SWC
SWC is a free, extensible Rust-based platform for tools that compile and bundle JavaScript and TypeScript. It transforms modern JavaScript and TypeScript into code intended for major browsers, and supports minification, WebAssembly transforms, and custom plugins. Its core API parses ECMAScript, TypeScript, and Flow syntax; the documentation describes that API as mainly useful to build-tool authors. Integrations include webpack, Rspack, and Jest, while Next.js, Parcel, and Deno are among the tools named as users. A WebAssembly module can transform code synchronously inside a browser. SWC can be installed as prebuilt binaries or built from source, with packages documented for npm, Yarn, pnpm, Bun, and Deno. The site states that it is 20x faster than Babel on one thread and 70x faster on four cores. The bundling documentation says that feature will be dropped in v2 and recommends SWC-based bundlers instead. It also warns that its polyfill usage mode is less efficient than Babel for certain dynamically computed property expressions.