Babel vs SWC

Babel is a JavaScript compiler that converts modern syntax into code compatible with current and older browsers or other environments. Its transformation pipeline is built from plugins, which users can combine into presets or write themselves. Babel provides transformers for the latest JavaScript and a React preset for JSX. It can also add features through third-party polyfills such as core-js, run codemods, and remove Flow or TypeScript type annotations; it does not check types. Source maps support debugging compiled output. The command-line interface can compile files or directories, watch for changes, and generate source maps. Installation documentation covers npm, Yarn, pnpm, and Bun. A standalone build can run in browsers and other non-Node.js environments, including on scripts marked text/babel or text/jsx, but the documentation recommends ahead-of-time transpilation with a Node.js build system for production. Babel is free, MIT-licensed, community-funded, and maintained by volunteers. The project directs support questions to GitHub Discussions, Slack, Stack Overflow, or Bluesky.

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.