SWC vs Turbopack

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.

Turbopack is an incremental JavaScript and TypeScript bundler written in Rust and built into Next.js. It supports the Pages Router and App Router for local development and is the default bundler in Next.js for basic use without configuration. It parallelizes work across CPU cores, caches results at the function level and persists them between runs. Lazy bundling processes only what the development server requests, which can reduce initial compile time and memory use. Its support includes JavaScript, TypeScript, ECMAScript, CommonJS, ESM and Babel configuration detection in Next.js 16, along with JSX, Fast Refresh and React Server Components for the App Router. CSS support includes global CSS, CSS Modules, nesting, PostCSS and Sass/SCSS, but not custom Sass functions. It also handles static image and font imports, JSON, aliases and custom extensions. Native bindings are available for Linux, macOS and Windows. Turbopack is included in Next.js with no separate price stated. It does not perform TypeScript type checking, and it does not support webpack plugins.