# Installing Red in a Virtual Environment¶

Virtual environments allow you to isolate red’s library dependencies, cog dependencies and python binaries from the rest of your system. It is strongly recommended you use this if you use python for more than just Red.

## Using venv¶

This is the quickest way to get your virtual environment up and running, as venv is shipped with python.

First, choose a directory where you would like to create your virtual environment. It’s a good idea to keep it in a location which is easy to type out the path to. From now, we’ll call it path/to/venv/ (or path\to\venv\ on Windows).

### venv on Linux or Mac¶

Create your virtual environment with the following command:

python3 -m venv path/to/venv/


And activate it with the following command:

source path/to/venv/bin/activate


Important

You must activate the virtual environment with the above command every time you open a new shell to run, install or update Red.

### venv on Windows¶

Create your virtual environment with the following command:

python -m venv path\to\venv\


And activate it with the following command:

path\to\venv\Scripts\activate.bat


Important

You must activate the virtual environment with the above command every time you open a new Command Prompt to run, install or update Red.

## Using pyenv virtualenv¶

Note

This is for non-Windows users only.

Using pyenv virtualenv saves you the headache of remembering where you installed your virtual environments. If you haven’t already, install pyenv with pyenv-installer.

First, ensure your pyenv interpreter is set to python 3.6.2 or greater with the following command:

pyenv version


Now, create a virtual environment with the following command:

pyenv virtualenv <name>


Replace <name> with whatever you like. If you forget what you named it, use the command pyenv versions.

Now activate your virtualenv with the following command:

pyenv shell <name>


Important

You must activate the virtual environment with the above command every time you open a new shell to run, install or update Red.

Once activated, your PATH environment variable will be modified to use the virtual environment’s python executables, as well as other executables like pip.

From here, install Red using the commands listed on your installation guide (Windows or Non-Windows).

Note

The alternative to activating the virtual environment each time you open a new shell is to provide the full path to the executable. This will automatically use the virtual environment’s python interpreter and installed libraries.

## Virtual Environments with Multiple Instances¶

If you are running multiple instances of Red on the same machine, you have the option of either using the same virtual environment for all of them, or creating separate ones.

Note

This only applies for multiple instances of V3. If you are running a V2 instance as well, You must use separate virtual environments.

The advantages of using a single virtual environment for all of your V3 instances are:

• When updating Red, you will only need to update it once for all instances (however you will still need to restart all instances for the changes to take effect)
• It will save space on your hard drive

On the other hand, you may wish to update each of your instances individually.

Important

Windows users with multiple instances should create separate virtual environments, as updating multiple running instances at once is likely to cause errors.