Python developers often end up with many virtualenvs scattered around the hard drive. Some belong to a particular project, some are general, some are created for a particular tool. Remembering the location of all environments, typing their paths to activate them and distinguishing which one is active now (for example if you happen to have foo/venv and bar/venv) can get tedious. There must be a better way!

$ vs-add ~/envs/numpy
Added /home/foo/envs/numpy as numpy
$ vs-add ~/envs/hg mercurial
$ vs-list
numpy      /home/foo/envs/numpy
mercurial  /home/foo/envs/hg
$ hg
hg: command not found
$ vs mer
[mercurial] $ hg st
abort: no repository found in ...
[mercurial] $ vs-expose hg
[mercuaial] $ vs-off
$ hg
abort: no repository found in ...

Prerequisites: a virtualenv with Python 3.

This will install virtualenv-switcher using pip and append the vs function and its completion configuration to your bash profile:

(vs-env) $ pip install virtualenv-switcher
(vs-env) $ vs-install >>~/.bashrc
(vs-env) $ source ~/.bashrc

Virtualenv Switcher keeps the paths to all virtualenvs as well as the path the directory where the commands are exposed in ~/.vs.conf. The file will be created if it doesn't exist. It can be edited by hand or via the following commands:

• vs-add -- to add a virtualenv to the configuration,
• vs-del -- to delete virtualenv from the configuration,
• vs-path -- to configure the path for exposing the commands.

• By default vs-install configures autocompletion of virtualenv names for vs and vs-del.
• When a virtualenv is activated its name becomes the name of the window in Tmux and some terminal emulators. This behavior can be disabled by editing the code that is added to the profile by vs-install.

• Virtualenvwrapper has some of the functionality of Virtualenv Switcher and quite a bit more on top. The scope of two packages is different: Virtualenvwrapper is a more complete virtualenv management solution whereas this package just makes switching between the environments as easy as possible and does not force any decisions on the user.