I just found an init script for puma : https://github.com/gitlabhq/gitlab-recipes/blob/master/init/sysvinit/debian/gitlab-puma
i think it can be improve a little with gitlab-rake command. I will try it soon if i have the time.
0x053A41EF03878A98.asc
Description: application/pgp-keys
signature.asc
Description: OpenPGP digital signature