@james
The hosted service at gitlab dot com does not run the Community Edition, but rather a custom subset of the proprietary enterprise edition. Also, it uses e.g. #Cloudflare, another proprietary platform.
For more backgrounds on the company itself, I only have https://git.sdf.org/humanacollaborator/humanacollabora/src/branch/master/gitlab-dot-com.md at hand ad-hoc. Not sure if it helps.
@derek