# Environment Variables

:::{envvar} RULES_PYTHON_BOOTSTRAP_VERBOSE

When `1`, debug information about bootstrapping of a program is printed to
stderr.
:::

:::{envvar} RULES_PYTHON_BZLMOD_DEBUG

When `1`, bzlmod extensions will print debug information about what they're
doing. This is mostly useful for development to debug errors.
:::

:::{envvar} RULES_PYTHON_DEPRECATION_WARNINGS

When `1`, the rules_python will warn users about deprecated functionality that will
be removed in a subsequent major `rules_python` version. Defaults to `0` if unset.
:::

:::{envvar} RULES_PYTHON_ENABLE_PYSTAR

When `1`, the rules_python Starlark implementation of the core rules is used
instead of the Bazel-builtin rules. Note this requires Bazel 7+.
:::

::::{envvar} RULES_PYTHON_EXTRACT_ROOT

Directory to use as the root for creating files necessary for bootstrapping so
that a binary can run.

Only applicable when {bzl:flag}`--venvs_use_declare_symlink=no` is used.

When set, a binary will attempt to find a unique, reusable, location within this
directory for the files it needs to create to aid startup. The files may not be
deleted upon program exit; it is the responsibility of the caller to ensure
cleanup.

Manually specifying the directory is useful to lower the overhead of
extracting/creating files on every program execution. By using a location
outside /tmp, longer lived programs don't have to worry about files in /tmp
being cleaned up by the OS.

If not set, then a temporary directory will be created and deleted upon program
exit.

:::{versionadded} VERSION_NEXT_PATCH
:::
::::

:::{envvar} RULES_PYTHON_GAZELLE_VERBOSE

When `1`, debug information from gazelle is printed to stderr.
:::

:::{envvar} RULES_PYTHON_PIP_ISOLATED

Determines if `--isolated` is used with pip.

Valid values:
* `0` and `false` mean to not use isolated mode
* Other non-empty values mean to use isolated mode.
:::

:::{envvar} RULES_PYTHON_REPO_DEBUG

When `1`, repository rules will print debug information about what they're
doing. This is mostly useful for development to debug errors.
:::

:::{envvar} RULES_PYTHON_REPO_DEBUG_VERBOSITY

Determines the verbosity of logging output for repo rules. Valid values:

* `DEBUG`
* `INFO`
* `TRACE`
:::

:::{envvar} RULES_PYTHON_REPO_TOOLCHAIN_VERSION_OS_ARCH

Determines the python interpreter platform to be used for a particular
interpreter `(version, os, arch)` triple to be used in repository rules.
Replace the `VERSION_OS_ARCH` part with actual values when using, e.g.
`3_13_0_linux_x86_64`. The version values must have `_` instead of `.` and the
os, arch values are the same as the ones mentioned in the
`//python:versions.bzl` file.
:::

:::{envvar} VERBOSE_COVERAGE

When `1`, debug information about coverage behavior is printed to stderr.
:::