Hi folks,
We are super excited to finally release the support for monorepo for GitLab!
This feature is available for new projects as well as already configured projects.
To find it, click on the “Analyze a new project” button from your homepage, then click on the “Setup a monorepo” at the bottom right.
Check our online documentation for more details and let us know what you think about this feature under this post 
Christophe - DevOps Platforms PM