Extra

Last updated on 2025-10-30 | Edit this page

Overview

Questions

  • How can we use pixi run start?
  • How to yank or un-yank a release?

Objectives

  • Learn how to use Pixi to run your project.
  • Learn how to make a release unavialable or undo that.

Introduction

After cloning a project, Install Pixi and Pixi makes it simple to run predefined tasks. If your pixi.toml (or pyproject.toml) contains a task named start, you can execute it directly using:

BASH 

gh repo clone priya-gitTest/greet_me && cd greet_me
curl -fsSL https://pixi.sh/install.sh | sh

If required, restart your shell:

BASH 

source ~/.bashrc

Verify that Pixi has been installed correctly.

BASH 

pixi --version

Now run

BASH 

pixi run start

OUTPUT 

✨ Pixi task (start): python -c 'from greet_me1 import happy; print(happy.greet_happy())'
Yay! happy day! 😀

This command will:

  • Ensure that the required environment is installed (creating or updating it if necessary).
  • Run the start task exactly as defined in your configuration file.

This provides a convenient and reproducible way to launch your project without needing to manually manage dependencies or commands. You can check the example project here

Yank and Un-yank

Occasionally, a release may contain an error or be uploaded by mistake. While PyPI and TestPyPI don’t allow deleting releases for security and reproducibility reasons, you can mark a specific version as yanked. Yanked releases remain accessible for reproducibility but are ignored by default when users install packages with pip install <package-name>.

Steps to Yank a version of your Python Package:

  • Log into your PyPI or TestPyPI account

  • Click on the your Projects from the top right location under your user-name. image

  • Select the right project /package from the options shown and click on the Manage button. image

  • Select the version you wish to yank and choose that option by clicking on the Options button and select Yank. image

  • You will be shown a pop-up. Fill the version nos and your releace will not be yanked. image

  • Once your release is yanked, it be be shown like below. image

  • You can also un-yank it, by clicking on the Options and clicking on Un-yank. image

  • When you do a pip install without stating an explicit verion and no un-yanked versions are available. You may get an error as shown below : image

You can read more about Yanking here and related PEP 592 specification here.

Further Reading

  1. Reproducible Machine Learning Workflows for Scientists with Pixi
Key Points
  • Define tasks such as start in your pixi.toml or pyproject.toml.
  • Use pixi run <task-name> to execute those tasks.
  • pixi run start ensures consistency and reproducibility when launching a project.
  • Yank a faulty release and provide useful comments for why you yanked it.