@sytse: it is one of the best documented and well packaged pieces of software these days. Specially in the Ruby world. Thank you for that. Gitlab really makes a difference.
Where others just distribute Docker images or directly nothing (because omg it is too hard to do proper packaging), Gitlab has nice packages for CentOS, Debian and Ubuntu (the distros that usually run in production servers).
We had an old install from git using mysql. Migrating to Omnibus and converting the DB to postgresql was painless. Surprisingly, it was a perfectly documented process without any pitfalls, or any outdated info. Omnibus packages are just wonderful. apt-get upgrade will just do all the necessary, DB migrations and restart all the components with almost zero downtime.
This proved to me that Gitlab actually gives uttermost care to the CE edition and that it is not just marketing.
So thank you Gitlab for being so awesome.