These web pages describe how to work with ATLAS offline code hosted in the git version control system.
If you have no experience with git at all, it’s worth checking out our collection of links in the Help with git section before anything else. There you’ll find a getting started guide for git itself and a leg up from SVN.
As well as using git as the source control management program, ATLAS uses the GitLab service at CERN to provide web based code management, and so we also suggest some GitLab bootstrap links.
On the 17th December 2018, ATLAS updated the Athena repository to make it public and open-source. If you are an ATLAS member and have forks or clones from before that date, please look at the instructions on the twiki
Before starting to follow each step of the workflow in detail, it’s useful to have an overview of the whole process, uncluttered from all minutiae. That’s what we give here, so refer back to this page if you start to lose a sense of where you are overall or why you are doing what you are doing.
You should start the detailed tutorial by setting up your environment and then following the rest of the material.
There is also a quick workflow section covering the most important steps of ATLAS code development (but lacking a lot of the explanations we give in the main tutorial).