Setting up gitlab is quite straight forward on archlinux, following this article.

The wiki article even mentions the procedure to run gitlab behind an apache https proxy. The only thing I’ve missed was the hint for changing the base url of gitlab so that a repository link would work with the correct domain instead of ‘localhost’.

For this it is necessary to change following section in gitlab.yml :

## GitLab settings
 gitlab:
 ## Web server settings (note: host is the FQDN, do not include http://)
 host: localhost
 port: 80
 https: false

Here you have to change localhost to your domain name.

Looks simple, but somethings you search a long time for simple solutions.