Environment Management in Python

Python's built-in venv module creates virtual environments, and virtualenv is the older, faster tool with extra features such as creating environments for other Python versions. pyenv installs and switches between many Python versions by building them from source and placing shims on your PATH. mise is a polyglot version manager: it installs Python alongside Node, Go and other runtimes, and switches per project directory, which suits repositories that mix languages.

uv, written in Rust by Astral, combines these jobs: it downloads prebuilt Python versions, creates virtual environments and manages project dependencies, and it is much faster than the traditional tools. For many projects it replaces pyenv, virtualenv and pip together. pyenv and mise remain useful when you already manage other runtimes the same way or need Python builds compiled locally. On Windows, see pyenv-win in the Microsoft Windows section.