Ubuntu Installation :: How To Build A .deb Package From Git

I work at a small company where we use to deploy things by just checking out the repo and copying stuff to production servers. This has to come to an end, enter .deb packages!

So I'm wondering what's the best procedure to do that. I already know how to create .deb packages, most of our stuff is Python and we're going to use python-support and cdbs. But how to maximally automate this?

We have a Git repo and ideally the whole thing should work like this:

* a tag is created in the Git repo (the version can be provided manually)

* some file like 'version.py' is created so that setup.py and the packaged software can refer to it and know the tag

* changelog is created from the Git commit logs

* the package is built (that's the part I've worked out - python-support and cdbs are involved here)

* optionally, the package is uploaded somewhere

There's a .deb package named 'git-buildpackage', is it suitable for this task? So far I can tell that it has one drawback - it looks for the 'debian/' directory in the root of the repository, which is not the case - our repo consists of several subdirectories, each contains a subproject that will be packaged independently.