I need to install GitLab in my ubuntu 12.04 64-bit

Found the following link but it doesn't work for me.

We need it to be a debian package to simplify installation in my company network

I know there is a bitnami installer but I don't like it (no trust with 3rd party)

Note: I don't want to accumulate scripts! I need a simple install one-click

GitLab is the ultimate git server manager for local networks and private companies