GitLab CI jobs run in a Docker image, defined here. To update that image (perhaps to install some more packages):
.gitlab-ci/Dockerfile
with the changes you want.gitlab-ci/run-docker.sh
and bump the version in TAG
.gitlab-ci/run-docker.sh
to build the new image, and launch a shell inside it.gitlab-ci/run-docker.sh --push
to upload the new image to the GNOME GitLab Docker registry.gitlab-ci.yml
(in the root of this repository) to use your new image