Debian 7 Wheezy 64bits

Installation instructions

wget -qO- https://dl.packager.io/srv/gitlabhq/gitlabhq/key | sudo apt-key add -
sudo wget -O /etc/apt/sources.list.d/gitlabhq.list \
  https://dl.packager.io/srv/gitlabhq/gitlabhq/7-4-stable/installer/debian/7.repo
sudo apt-get update
sudo apt-get install gitlab-ce

Note: You might need to apt-get install wget apt-transport-https for the above instructions to work.

More details can be found at https://github.com/gitlabhq/gitlab-recipes/tree/master/install/pkgr .