pixi is a general multi-languge, multi-platform package manager. I am using it now on my new macbook neo as a homebrew _replacement_. Yes, it goes beyond python and allows you to install git, jj, fzf, cmake, compilers, pandoc, and many more.
For python, pixi uses conda-forge and PyPI as package repos and relies on uv's rattler dependency resolver. pixi is as fast as uv (it uses fast code path from uv) but goes further beyond python wheels.
For detail see [0] or google it :-)
There is a good chunk of overlap but mise predominately pulls from github releases artifacts/assets and pixi uses conda packages. While mise can use conda packages, the mise-conda backend is still experimental. I don't think github releases or conda packages are better than the other, they both have tradeoffs.
Pixi is very python focused, it's both a tool manager and a library dependency manager (see uv/pip). Mise considered library dependency an anti-goal for a long time, while I don't see that on the website anymore I haven't seen any movement to go into that space.
