Skulpt vs SWC

Skulpt is a free, web-based implementation of Python that executes code entirely in the browser. It requires no preprocessing, plugins, or server-side support. The online editor provides indentation, standard editing shortcuts, and keyboard commands to run all code or only a selection. Developers can embed Skulpt in a webpage or HTML project by loading `skulpt.js` or `skulpt-min.js` together with `skulpt-stdlib.js`, and they can create and host custom modules. The usage guide also describes embedding Trinket examples in an iframe, remixing them, and saving work to a free Trinket account. Skulpt is presented for learning and teaching Python, with a project gallery for educational examples. Its master branch uses Python 3.7.3 grammar, while Python 2 remains available for projects needing it. Documentation says language coverage is incomplete, with some features missing or partial. The runtime may use MIT or PSFLv2 licensing. CLI and API access are listed.

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.