Comment by PufPufPuf

Mise installs itself as a static binary actually (but it's of course packaged in many registries), and while there are some third party registries it delegates to for some packages (aqua, asfd), most stuff I have installed is either built-in, or from PyPI, npm or GitHub, i.e. directly published by the upstream maintainers. More info: https://mise.jdx.dev/dev-tools/backends/