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Comment by simonw | Hacker News Reader

How long should it take for "wasmer run python/python" to start showing me output? It's been hung for a while for me now (I upgraded to wasmer 6.1.0-rc.5).

"wasmer run python/python@=0.2.0" on the same machine gets me into Python 3.12.0 almost instantly.

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Compilation with LLVM takes quite a while (the final release will show a spinner...).

So please wait a bit - subsequent runs will be fast, since compiled Python will be cached.

Oh so it's actually compiling everything on my machine?

Any chance `wasmer run python/python` might download a pre-compiled version in the future?

Yeah, that's mentioned as a small side note in the blog post - we are working on it, and will hopefully have it ready in a week or two!

OK got there in the end! I didn't time it but felt like around 10 minutes or more.

It did give me one warning message:

  % wasmer run python/python
  Python 3.13.0rc2 (heads/feat/dl-dirty:152184da8f, Aug 28 2025, 23:40:30) [Clang 21.1.0-rc2 (git@github.com:wasix-org/llvm-project.git 70df5e11515124124a4 on wasix
  Type "help", "copyright", "credits" or "license" for more information.
  warning: can't use pyrepl: No module named 'msvcrt'
  >>>

That sounds like the compilation is accidentally triggering this old frustration [0].

[0] https://github.com/python/cpython/issues/131189

Compilation was slow for me on macOS too.

We'll improve this very soon, right now the experience is less than ideal.

Ideally we would download the compiled artifacts instead of compiling as Simon commented... it will be a much better experience for everyone!

It says the same thing in the pyodide repl for what it's worth.

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