Pyodide: a Python distribution based on WebAssembly

(github.com)

41 points | by tosh 3 days ago

10 comments

  • fzumstein 6 minutes ago
    Pyodide powers xlwings Lite, a free Excel add-in that you can install from Excel’s add-in store with a single click. It outperforms Microsoft’s official Python in Excel solution in every coceivable way: price, privacy, speed, can install packages, can access the internet, can access local files, doesn’t have a usage quota, can automate Excel and create native UDFs. See https://lite.xlwings.org
  • simonw 2 hours ago
    Pyodide is one of the hidden gems of the Python ecosystem. It's SO good at what it does, and it's nearly 8 years old now so it's pretty mature.

    I love using Pyodide to build web UIs for trying out new Python libraries. Here's one I built a few weeks ago to exercise my pure-Python SQLite AST parser, for example: https://tools.simonwillison.net/sqlite-ast

    It's also pretty easy[1] to get C or Rust libraries that have Python bindings compiled to a WebAssembly wheel that Pyodide can then load.

    Here's a bit of a nutty example - the new Monty Python-like sandbox library (written in Rust) compiled to WASM and then loaded in Pyodide in the browser: https://simonw.github.io/research/monty-wasm-pyodide/pyodide...

    [1] OK, Claude Code knows how to do it.

    • iamcreasy 1 hour ago
      How do you call those C/Rust libraries compiled from to webassembly from Python/Pyodide?
      • simonw 1 hour ago
        You have to turn them into WebAssembly wheels, then you can import them as if they were regular Python modules.
  • QuadmasterXLII 2 hours ago
    It works surprisingly well in terms of writing python for native execution, and then trying to share on the web and having it Just Work TM. Unfortunately, when I want python it's because I want numpy, scipy and friends, and once you bring them on board pyodide load times are long. As an example comparison: a face turning octahedron puzzle in python + pyodide, loads in 10 seconds https://cubes.hgreer.com/fto.html . Meanwhile, a megaminx puzzle in javascript (statically generated by python) loads in 200 ms https://cubes.hgreer.com/ssg/output.html
  • yjftsjthsd-h 51 minutes ago
    That is very cool. Has anyone made a nice beginner's learning environment out of it? Seems like it would solve some of the extra friction that makes it hard to get started.
    • cfu28 21 minutes ago
      I played around with it to build a little "intro to python" walkthrough on my blog a while back. It worked surprisingly well! I had a little trouble giving users the ability to ctrl-c if they accidentally wrote an infinite loop though lol (piodide supports it I just didn't implement it): https://cfu288.com/blog/2024-05_cwc-intro-to-python/
    • wisty 25 minutes ago
      Jupyterlite - a lot of jupyter trial versions use it.
  • jasiek 58 minutes ago
    I've used it to put together a browser app to program walkie-talkies: https://codeplug.org
  • devsda 2 hours ago
    There's also xeus-cpp which is cpp based on wasm. Xeus-cpp and pyodide are the backends for Jupyterlite [1] kernels in browser.

    It's actually a very good way to teach coding in python/c++(11, 17 or even 23), explore language features or your own library within browser and allow students to execute code by hosting just some static html pages and some assets without any backend.

    1. https://jupyter.org/try-jupyter/lab/

  • ianberdin 1 hour ago
    Yea, I even built online ide based on Pyodide. Insane peace of software. You can try here: playcode.io/python
  • jacob019 3 hours ago
    Anyone using it with nodejs to make a sandbox for code agents?
    • simonw 2 hours ago
      I've done some experiments along those lines with Pyodide in Deno: https://til.simonwillison.net/deno/pyodide-sandbox
    • b89kim 2 hours ago
      ChatGPT's Canvas uses Pyodide for sandboxing, but it's not designed for coding agents. Node.js environment is usually better for agents. Pyodide restricts server-side functionality, and fetching external URLs often needs proxying due to sandbox. By the way, pyodide is still good option for interactive visualizer or deploying small webapps require data processing.
    • jcheng 3 hours ago
      For that purpose I think most people are using bubblewrap or seatbelt/sandbox-exec with CPython.
  • yawnxyz 3 hours ago
    no but it works great in conjunction with observable and d3js for pretty interactives!
  • anarhackist 3 hours ago
    [dead]