Run the CI in a custom container

[qdeslandes]

The CI jobs run in Docker containers, depending on the distribution the project needs to be built/tested on. Installing the dependencies and configuring the build container is long and account for most of the CI duration.

The CI duration could be reduced by using a container that already provides the required dependencies. We could also run each major step (build, test…) in a separate container to provide more granular check status on PRs.

Using a custom container, the workflow could be the following:

• Build the containers (Ubuntu, Fedora, x64, arm64…)
• Push the container to the repository's register(GHCR)
• Run the build step in a container
• Run the test step in a container
• More check…

See better_ci for a PoC.