[tmaczukin]

You can use images hosted on GitLab's Container Registry. Especially - you can use such images as the base for CI/CD jobs running on the same GitLab instance.

It was possible since very erly state of GitLab's Container Registry. The problem was when one wanted to use images created from internal or private projects, which require previous authentication. Support for such workflow was added (partially) in GitLab Runner 0.6, and with GitLab Runner 1.8 (late 2016) it's possible to use any private registry with GitLab CI jobs. And private images from the same GitLab instance are accessible without any additional work that needs to be made by the user - until the user who triggered a job has access to the project where requested image is stored.

Details can be found at https://docs.gitlab.com/ee/ci/docker/using_docker_images.htm....