Environment Variables

pip-tools supports a number of environment variables as ways of customizing behavior.

pip Environment Variables

pip is used inside of pip-tools.

As a result, all of the environment variables supported by pip are supported when using pip-tools. For example, PIP_BUILD_CONSTRAINT can be used to control the environment used for package builds.

See the pip documentation on environment variables for full details.

pip-tools Environment Variables

CUSTOM_COMPILE_COMMAND

This setting controls the command printed in the header for files generated and updated by pip-compile. Set it in order to replace the default behavior – which is to use the command which was run – with a custom command.

PIP_TOOLS_CACHE_DIR

The directory to use for pip-tools’ caching. Defaults to a directory named pip-tools/ inside of the user’s cache directory. This can also be set by the --cache-dir option.

PIP_TOOLS_RESOLVER

Select which resolver to use, either legacy or backtracking. The legacy resolver will be removed in a future release. This can also be set by the --resolver option.