GitLab might move to a single Rails codebase

This post proposes merging the gitlab-ce and gitlab-ee Rails repositories into a single `gitlab` repository. The motivation is to eliminate duplicated work, reduce conflicts during feature development and release preparation, and save engineering time currently spent on managing two separate codebases. The proposed change involves moving all frontend assets to be open-sourced under MIT license, placing proprietary backend code in an `/ee` directory, and merging documentation. The gitlab-ce distribution will remain open source, and other projects will be unaffected. Downsides include users cloning a larger repository and the presence of unpopulated database tables in the CE distribution.