GitLab is a platform for managing code, comparable to GitHub: it stores repositories, shows their change history, lets changes be reviewed, and runs pipelines. The Application Platform operates its own GitLab at gitlab.application-platform.com, where you sign in with the same account as on the platform.
How your projects are laid out in GitLab
A group is a folder for several repositories with shared members and permissions. Every organization has a group and every project a subgroup under orgs/<organization>/<project>/ with one repository per component, for example backend and the name of your app, plus local-configuration with the configuration for editors and AI agents and gitops-configuration, which describes which version runs with which settings on dev and production.
The platform maintains the files it generates there, above all .gitlab-ci.yml and env/*.generated.env; you do not edit these by hand, and everything else belongs to you.
What you find in GitLab
The file view shows the current code and the list of commits. The branch main is the main state; whatever arrives there is rolled out to dev by the pipeline. Under Merge Requests, changes can be reviewed before they land on main, which is possible but not required. Under CI/CD → Pipelines the pipelines run, and in the container and package registry the pipeline stores Docker images and packages, see Libraries.
Why you open GitLab day to day
Cloning, committing, and pushing happen in your editor, in the terminal, or through an AI agent, see Save changes and publish. You open GitLab itself to watch pipelines and start the production job via the play button, to read the log when a pipeline is red, and to comment on and approve merge requests. The repository links are in the project overview of the platform.
What the pipelines do in detail is described in What are pipelines?.