...
Source code is hosted at:
https://git-wip-us.apache.org/repos/asf/incubator-cloudstack.git
You can send in diffs of your changes to the Cloudstack development mailing list, where your diffs will be reviewed and committed to the master branch that syncs up often with the external public git branch.
The master git branch is what Apache Cloudstack developers work with. To clone this branch, you will need to do -
git clone https://git-wip-us.apache.org/repos/asf/incubator-cloudstack.git
You may want to pull a specific sub-branch of cloudstack-oss. To do this, you will need to first pull the cloudstack-oss branch using the git clone command above, and then, do -
...