# Installation

## Supported Shells

virtualenvwrapper is a set of shell functions defined in Bourne shell compatible syntax. Its automated tests run under these shells on OS X and Linux:

- `bash`

- `ksh`

- `zsh`

It may work with other shells, so if you find that it does work with a shell not listed here please let me know. If you can modify it to work with another shell without completely rewriting it, then send a pull request through the bitbucket project page. If you write a clone to work with an incompatible shell, let me know and I will link to it from this page.

### Windows Command Prompt

David Marble has ported virtualenvwrapper to Windows batch scripts, which can be run under Microsoft Windows Command Prompt. This is also a separately distributed re-implementation. You can download virtualenvwrapper-win from PyPI.

### MSYS

It is possible to use virtualenv wrapper under MSYS with a native Windows Python installation. In order to make it work, you need to define an extra environment variable named `MSYS_HOME` containing the root path to the MSYS installation.

    export WORKON_HOME=$HOME/.virtualenvs
    export MSYS_HOME=/c/msys/1.0
    source /usr/local/bin/virtualenvwrapper.sh

or:

    export WORKON_HOME=$HOME/.virtualenvs
    export MSYS_HOME=C:\msys\1.0
    source /usr/local/bin/virtualenvwrapper.sh

Depending on your MSYS setup, you may need to install the MSYS mktemp binary in the `MSYS_HOME/bin` folder.

### PowerShell

Guillermo López-Anglada has ported virtualenvwrapper to run under Microsoft’s PowerShell. We have agreed that since it is not compatible with the rest of the extensions, and is largely a re-implementation (rather than an adaptation), it should be distributed separately. You can download virtualenvwrapper-powershell from PyPI.

## Python Versions

virtualenvwrapper is tested under Python 2.7-3.6.

## Basic Installation

virtualenvwrapper should be installed into the same global site-packages area where virtualenv is installed. You may need administrative privileges to do that. The easiest way to install it is using pip:

    $ pip install virtualenvwrapper

or:

    $ sudo pip install virtualenvwrapper

Warning

virtualenv lets you create many different Python environments. You should only ever install virtualenv and virtualenvwrapper on your base Python installation (i.e. NOT while a virtualenv is active) so that the same release is shared by all Python environments that depend on it.

An alternative to installing it into the global site-packages is to add it to your user local directory (usually ~/.local).

    $ pip install --user virtualenvwrapper

## Shell Startup File

Add three lines to your shell startup file (`.bashrc`, `.profile`, etc.) to set the location where the virtual environments should live, the location of your development project directories, and the location of the script installed with this package:

    export WORKON_HOME=$HOME/.virtualenvs
    export PROJECT_HOME=$HOME/Devel
    source /usr/local/bin/virtualenvwrapper.sh

After editing it, reload the startup file (e.g., run `source ~/.bashrc`).

### Lazy Loading

An alternative initialization script is provided for loading virtualenvwrapper lazily. Instead of sourcing `virtualenvwrapper.sh` directly, use `virtualenvwrapper_lazy.sh`. If `virtualenvwrapper.sh` is not on your `$PATH`, set `VIRTUALENVWRAPPER_SCRIPT` to point to it.

    export WORKON_HOME=$HOME/.virtualenvs
    export PROJECT_HOME=$HOME/Devel
    export VIRTUALENVWRAPPER_SCRIPT=/usr/local/bin/virtualenvwrapper.sh
    source /usr/local/bin/virtualenvwrapper_lazy.sh

Warning

When the lazy-loading version of the startup script is used, tab-completion of arguments to virtualenvwrapper commands (such as environment names) is not enabled until after the first command has been run. For example, tab completion of environments does not work for the first instance of workon.

## Quick-Start

1. Run: `workon`

2. A list of environments, empty, is printed.

3. Run: `mkvirtualenv temp`

4. A new environment, `temp` is created and activated.

5. Run: `workon`

6. This time, the `temp` environment is included.

## Configuration

virtualenvwrapper can be customized by changing environment variables. Set the variables in your shell startup file before loading `virtualenvwrapper.sh`.

### Location of Environments

The variable `WORKON_HOME` tells virtualenvwrapper where to place your virtual environments. The default is `$HOME/.virtualenvs`. If the directory does not exist when virtualenvwrapper is loaded, it will be created automatically.

### Location of Project Directories

The variable `PROJECT_HOME` tells virtualenvwrapper where to place your project working directories. The variable must be set and the directory created before mkproject is used.

See also

- Project Management

### Project Linkage Filename

The variable `VIRTUALENVWRAPPER_PROJECT_FILENAME` tells virtualenvwrapper how to name the file linking a virtualenv to a project working directory. The default is `.project`.

See also

- Project Management

### Enable Project Directory Switching

The variable `VIRTUALENVWRAPPER_WORKON_CD` controls whether the working directory is changed during the post activate phase. The default is `1`, to enable changing directories. Set the value to `0` to disable this behavior for all invocations of `workon`.

See also

- workon

### Location of Hook Scripts

The variable `VIRTUALENVWRAPPER_HOOK_DIR` tells virtualenvwrapper where the user-defined hooks should be placed. The default is `$WORKON_HOME`.

See also

- Per-User Customization

### Location of Hook Logs

The variable `VIRTUALENVWRAPPER_LOG_FILE` tells virtualenvwrapper where the logs for the hook loader should be written. The default is to not log from the hooks.

### Python Interpreter, virtualenv, and $PATH

During startup, `virtualenvwrapper.sh` finds the first `python` and `virtualenv` programs on the `$PATH` and remembers them to use later. This eliminates any conflict as the `$PATH` changes, enabling interpreters inside virtual environments where virtualenvwrapper is not installed or where different versions of virtualenv are installed. Because of this behavior, it is important for the `$PATH` to be set before sourcing `virtualenvwrapper.sh`. For example:

    export PATH=/usr/local/bin:$PATH
    source /usr/local/bin/virtualenvwrapper.sh

To override the `$PATH` search, set the variable `VIRTUALENVWRAPPER_PYTHON` to the full path of the interpreter to use and `VIRTUALENVWRAPPER_VIRTUALENV` to the full path of the `virtualenv` binary to use. Both variables must be set before sourcing `virtualenvwrapper.sh`. For example:

    export VIRTUALENVWRAPPER_PYTHON=/usr/local/bin/python
    export VIRTUALENVWRAPPER_VIRTUALENV=/usr/local/bin/virtualenv
    source /usr/local/bin/virtualenvwrapper.sh

### Default Arguments for virtualenv

If the application identified by `VIRTUALENVWRAPPER_VIRTUALENV` needs arguments, they can be set in `VIRTUALENVWRAPPER_VIRTUALENV_ARGS`. The same variable can be used to set default arguments to be passed to `virtualenv`. For example, set the value to `--no-site-packages` to ensure that all new environments are isolated from the system `site-packages` directory.

    export VIRTUALENVWRAPPER_VIRTUALENV_ARGS='--no-site-packages'

### Temporary Files

virtualenvwrapper creates temporary files in `$TMPDIR`. If the variable is not set, it uses `/tmp`. To change the location of temporary files just for virtualenvwrapper, set `VIRTUALENVWRAPPER_TMPDIR`.

### Site-wide Configuration

Most UNIX systems include the ability to change the configuration for all users. This typically takes one of two forms: editing the skeleton files for new accounts or editing the global startup file for a shell.

Editing the skeleton files for new accounts means that each new user will have their private startup files preconfigured to load virtualenvwrapper. They can disable it by commenting out or removing those lines. Refer to the documentation for the shell and operating system to identify the appropriate file to edit.

Modifying the global startup file for a given shell means that all users of that shell will have virtualenvwrapper enabled, and they cannot disable it. Refer to the documentation for the shell to identify the appropriate file to edit.

## Upgrading to 2.9

Version 2.9 includes the features previously delivered separately by `virtualenvwrapper.project`. If you have an older verison of the project extensions installed, remove them before upgrading.

## Upgrading from 1.x

The shell script containing the wrapper functions has been renamed in the 2.x series to reflect the fact that shells other than bash are supported. In your startup file, change `source /usr/local/bin/virtualenvwrapper_bashrc` to `source /usr/local/bin/virtualenvwrapper.sh`.