Brython vs js_of_ocaml
Brython
brython.infojs_of_ocaml
ocsigen.orgSide by side
| Figure | Brython | js_of_ocaml |
|---|---|---|
| Price from | — | Free |
| Free plan | — | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | Yes |
| Linux | — | Yes |
| iOS | Yes | — |
| Android | Yes | — |
| API | — | Yes |
| Self-hosted | Yes | — |
| Plans published | 0 | 1 |
| Spec score · Code Transpilers | 7.9 (#10) | 8.4 (#5) |
| Browser support | The FAQ says Brython supports all modern browsers, including browsers on smartphones. | Generated JavaScript supports modern browsers that implement ECMAScript 2020, including Chrome 80+, Firefox 74+, Safari 13.4+, and Edge 80+. |
| Installation | Brython can be used from jsDelivr or cdnjs without installation, or installed locally with pip or a GitHub release archive. | The compiler and related packages are installable through opam, the OCaml package manager. |
| JavaScript interoperability | Brython provides ways for Python code to use JavaScript objects and libraries. | The library provides a typed interface for bridging OCaml and JavaScript values, with PPX syntax for JavaScript properties, methods, constructors, and objects. |
| Purpose | Brython implements Python 3 in the browser and lets developers run Python code in HTML pages. | js_of_ocaml compiles OCaml bytecode programs to JavaScript for use in browsers and Node.js. |
| Security and compliance | The official pages reviewed provide no stated security certification or compliance claim. | The project pages reviewed do not state security certifications or compliance attestations. |
Plans
In their own words
js_of_ocaml
js_of_ocaml compiles OCaml bytecode programs into JavaScript for browsers and Node.js. It works with an existing OCaml installation and does not require libraries to be recompiled. Installation is available through opam, while Dune supports separate compilation in development and whole-program compilation in release builds. Whole-program compilation performs global dead-code elimination and cross-module optimization. The library provides a typed bridge between OCaml and JavaScript, including PPX syntax for properties, methods, constructors and objects. Browser bindings cover the DOM, Fetch, WebSockets, WebGL, workers and typed arrays. Optional packages add Lwt support, TyXML, JSON derivation and an OCaml toplevel in the browser. Documented targets include Node.js 18 or later, QuickJS-NG and modern ECMAScript 2020 browsers, including Chrome 80+, Firefox 74+, Safari 13.4+ and Edge 80+. Requirements include OCaml 4.13–5.5, Dune 3.20 or later and Menhir. The project is free and open source.