The Hockeypuck project is hosted in Launchpad.
Post feature ideas, defects and questions to the Launchpad project bug tracker.
Leading edge development happens in the trunk branch, lp:hockeypuck. Keeping a stable trunk (building & passing unit tests) is priority.
To contribute a patch, push to a local branch with your changes, for example:
$ bzr push lp:~user/hockeypuck/my-contribution
Then create a request to merge the branch to lp:hockeypuck (or release target branch). This is similar to a pull request in Github.
Hockeypuck trunk is mirrored in Github mostly for backup purposes, and may lag the Launchpad trunk. I may not be able to directly merge pull requests through Github. Collaboration through Launchpad is certainly preferred.
Discuss the project on the hockeypuck-dev mailing list. You'll need to join the open hockeypuck-dev team in Launchpad in order to register your email address.