I meant the host where the repository is kept and where people upload new versions to and buildds new builds of existing source packages. Requirements for that are reprepro installed, a 9.1 PG database, and some way to upload stuff. That's most likely just ssh (and maybe rsync).
The web frontend is mostly plain files served, plus some CGI scripts (DBD::Pg). In case these are separate hosts, the files part would get rsynced over.
Buildds would need to talk to the DB using the queries I was mentioning (probably via a CGI) to figure out what needs building.
I think putting the repository part in place would be possible quite easily. We would then start by manually building things, and set up buildds as we like.
Btw, I'm writing this from the hospital - mother and new boy are well and we are very happy :-)