Shims

After installation Rye places two shims on your PATH: python and python3. These shims have specific behavior that changes depending on if they are used within a Rye managed project or outside.

Inside a Rye managed project they resolve to the Python interpreter of the virtualenv. This means that even if you do not enable the virtualenv, you can just run python in a shell, and it will automatically operate in the right environment.

Outside a Rye managed project it typically resolves to your system Python, though you can also opt to have it resolve to a Rye managed Python installation for you. This is done so that it's not disruptive to your existing workflows which might depend on the System python installation.

Global Shims

+++ 0.9.0

To enable global shims, you need to enable the global-python flag in the config.toml file:

rye config --set-bool behavior.global-python=true

Afterwards if you run python outside of a Rye managed project it will spawn a Python interpreter that is shipped with Rye. It will honor the closest .python-version file for you. Additionally you can also explicitly request a specific Python version by adding +VERSION after the python command. For instance this runs a script with Python 3.8:

python +3.8 my-script.py

!!! Note

Selecting a specific Python version this way only works outside of
Rye managed projects.  Within Rye managed projects, the version needs
to be explicitly selected via `.python-version` or with the
`requires-python` key in `pyproject.toml`.