Frequently Encountered Pipenv Problems

Pipenv is constantly being improved by volunteers, but is still a very young project with limited resources, and has some quirks that needs to be dealt with. We need everyone’s help (including yours!).

Here are some common questions people have using Pipenv. Please take a look below and see if they resolve your problem.


Make sure you’re running the newest Pipenv version first!

☤ Your dependencies could not be resolved

Make sure your dependencies actually do resolve. If you’re confident they are, you may need to clear your resolver cache. Run the following command:

pipenv run pipenv-resolver --clear

and try again.

If this does not work, try manually deleting the whole cache directory. It is usually one of the following locations:

  • ~/Library/Caches/pipenv (macOS)
  • %LOCALAPPDATA%\pipenv\pipenv\Cache (Windows)
  • ~/.cache/pipenv (other operating systems)

Pipenv does not install prereleases (i.e. a version with an alpha/beta/etc. suffix, such as 1.0b1) by default. You will need to pass the --pre flag in your command, or set

allow_prereleases = true

in your Pipfile.

☤ No module named <module name>

This is usually a result of mixing Pipenv with system packages. We strongly recommend installing Pipenv in an isolated environment. Uninstall all existing Pipenv installations, and see ☤ Homebrew Installation of Pipenv to choose one of the recommended way to install Pipenv instead.

☤ My pyenv-installed Python is not found

Make sure you have PYENV_ROOT set correctly. Pipenv only supports CPython distributions, with version name like 3.6.4 or similar.

☤ Pipenv does not respect pyenv’s global and local Python versions

Pipenv by default uses the Python it is installed against to create the virtualenv. You can set the --python option, or $PYENV_ROOT/shims/python to let it consult pyenv when choosing the interpreter. See ☤ Specifying Versions of a Package for more information.

If you want Pipenv to automatically “do the right thing”, you can set the environment variable PIPENV_PYTHON to $PYENV_ROOT/shims/python. This will make Pipenv use pyenv’s active Python version to create virtual environments by default.

☤ ValueError: unknown locale: UTF-8

macOS has a bug in its locale detection that prevents us from detecting your shell encoding correctly. This can also be an issue on other systems if the locale variables do not specify an encoding.

The workaround is to set the following two environment variables to a standard localization format:

  • LC_ALL
  • LANG

For Bash, for example, you can add the following to your ~/.bash_profile:

export LC_ALL='en_US.UTF-8'
export LANG='en_US.UTF-8'

For Zsh, the file to edit is ~/.zshrc.


You can change both the en_US and UTF-8 part to the language/locale and encoding you use.

☤ /bin/pip: No such file or directory

This may be related to your locale setting. See ☤ ValueError: unknown locale: UTF-8 for a possible solution.

shell does not show the virtualenv’s name in prompt

This is intentional. You can do it yourself with either shell plugins, or clever PS1 configuration. If you really want it back, use

pipenv shell -c

instead (not available on Windows).

☤ Pipenv does not respect dependencies in

No, it does not, intentionally. Pipfile and serve different purposes, and should not consider each other by default. See ☤ Pipfile vs for more information.