02_multi_environment

Step Two: Multi-environment Projects

In this step, we will create a project that manages conflicting dependencies (Legacy vs Modern) using Pixi Features and Environments.

1. Initialization

Initialize a new Pixi project:

pixi init

2. Base Dependencies

Add dependencies shared by all environments:

pixi add "python=3.9.*" colorama

3. Defining Features

Features allow you to group dependencies that are essentially "optional" or "variants".

Create a "legacy" feature with older packages:

pixi add --feature legacy "pandas<1.5" "numpy<1.22"

Create a "modern" feature with newer packages:

pixi add --feature modern "pandas>=2.0" "numpy>=1.24"

4. Defining Environments

Now we need to tell Pixi how to combine these features into environments.

pixi workspace environment add modern --feature modern
pixi workspace environment add legacy --feature legacy

Note, your features do not have to have the same name! You can have many features per environment and even have quite complex solve groups. But this is the basic steps.

5. Running Code

Now try running the conflicting scripts in their respective environments!

Run Legacy:

pixi run -e legacy python legacy_script.py

Run Modern:

pixi run -e modern python modern_script.py

You can view the reference configuration in solution.toml.