I like that people are discussing alternatives to #github (yet again), and I also am fond of #gitlab and what they've achieved in the past.
Having said that, I had to work with GitLab recently, and it was a nightmare. It's just trying too hard to be too many things at once & failing to be a serious contender for any of these purposes.
Please also consider alternatives like Gogs or Gitea. They both work incredibly well and are scaling to any size https://gogs.io https://gitea.io
@moritzheiber
Gogs is poorly maintained, and Gitea appears understaffed to handle the huge number of issues already open on GH. I self-host Gitea and I'm mostly happy, but I think I'd have been better off self-hosting Gitlab. :/
@moritzheiber @cathal consider gitbucket https://github.com/gitbucket/gitbucket . large active community, regular releases for years. easy deploy for self hosting.