Pixi

Pixi is a modern package manager that simplifies the installation of scientific software. It’s built on top of the conda-forge ecosystem but is significantly faster and provides better dependency resolution.

Why Pixi?

• Fast: 5-10x faster than conda for most operations
• Reproducible: Uses lock files to ensure exact environment reproduction
• Task Runner: Built-in task management (like npm scripts)
• Modern Design: Clean CLI with better error messages
• Conda Compatible: Uses the conda-forge repository

Installation

Follow the installation instructions on the official Pixi website. The installer will set up Pixi and configure your PATH automatically.

Getting Started

Initialize a new project:

pixi init
pixi add python
pixi shell

Add packages:

pixi add numpy pandas matplotlib

Define and run tasks in pixi.toml:

[tasks]
dev = "python main.py"
test = "pytest tests/"

Run tasks:

pixi run dev
pixi run test

Advantages Over Conda

• Much faster package resolution and installation
• Lock files ensure reproducibility by default
• Better support for managing multiple projects
• Built-in task runner eliminates need for separate tools

Tips

• Use pixi shell to activate the environment
• Define common tasks in pixi.toml for easy project workflows
• Lock files (pixi.lock) should be committed to version control
• Use pixi global install for system-wide tools