also some things don't seem to belong there at all, for example $site is currently autodetected from ip address whereas I think it should be set by provisioning. e.g. by writing /etc/wikimedia/site or sth like that and puppet picks up that

Change 311223 had a related patch set uploaded (by Giuseppe Lavagetto):
realm: convert main_ipaddress and site into facts

https://gerrit.wikimedia.org/r/311223

Change 311223 abandoned by Giuseppe Lavagetto:
realm: convert main_ipaddress and site into facts

https://gerrit.wikimedia.org/r/311223

This is actually not going to happen: the future parser and puppet 4 have the concept of "directory manifests" that allows us to have a global piece of code to prepend to site.pp.

And since the file has shrunk considerably from its glory days and is now mostly ok (although there is a ton of labs-specific boilerplate that I'd move somewhere else, like in a labs-specific directory environment).

So, declining the ticket now.