We use a few websites to manage our code and bugs, and while it is possible to get by without signing up for these sites, it’s strongly recommended that you create accounts on these websites.


Many A-Team projects are hosted on GitHub. GitHub provides hosting for our source code, as well as tools we use for collaboration and code review. GitHub is based on Git, a distributed version control system that lets us track the changes we make to our code.

Once you’ve created a GitHub account, you can check out the GitHub help site for guides on the basics of using Git and GitHub.

See also

Mozilla on GitHub
Mozilla’s organization account on GitHub.

Mercurial and Mozilla-Central

Much of our other build & test code lives inside mozilla-central, a Mercurial repository which also contains the source code to Firefox. Check out Mercurial for Mozillians for guides on installing and using Mercurial.

To be able to commit to the mozilla-central repository directly, you will need to sign a contributor’s agreement and be vouched for by a module owner. You probably don’t need to worry about this initially: just clone the repository, test your changes locally, and let other people push your patches for you.

If you find that you’re working on a lot of stuff within this code base, you’ll want to apply for committer access so you can push code to try or an integration branch like mozilla-inbound.


Bugzilla is the issue-tracking system that the entire Mozilla Project uses. The vast majority of A-Team projects use Bugzilla to keep track of any planned changes to or bugs in our projects.

As a new contributor, Bugzilla is a useful tool for finding known issues that you can help fix or finding planned work you want to take on. In order to assign a bug to yourself or to post a comment on a bug, you’ll need to create a Bugzilla account. An account also allows you to “CC” yourself on bugs that you are interested in, so that you receive emails when those bugs are changed.

After you’ve been using Bugzilla for a while as a community member, it’s worthwhile applying for expanded permissions. The editbugs permission allows you to assign bugs to yourself and resolve them, for example. See the Bugzilla Permissions Page for details. Note that new employees get this permission automatically; there’s no need to ask for it.


It’s highly recommended to add your IRC nickname to your real name within Bugzilla to make it easy for others to auto-complete your name.

The standard format is to follow your real name with your IRC name, preceeded by a colon, surrounded by square brackets. For example: Cave Johnson [:withthelemons].