Assistance for customizing Containerfiles

[gendergap]

My company has an existing infrastructure to customize container images (e.g. inject package mirrors, company certs or proxy information). The infrastructure is based on container files (e.g. Dockerfile) and Docker Buildkit.
In the past, we also used this infrastructure to customize the AWX EE images we were using internally. Every few months I would take another look at the image file in this repository and cherry-pick some of the upstream changes into ours.

Some time ago, this repository switched to using ansible-builder, which uses a different approach to get to the same result. Probably works fine, but there is no plain container file available anymore to reference.

How do people work with this for customizations? I see that we could create a separate build chain for our internal AWX EE images that does not use Docker BuildKit but ansible-builder. Or one could reverse engineer how a container definition would need to look like that has the same result as the configuration in this repository.

Does anybody have some insight on how they are doing it?

[seadoox]

I use ansible-builder create -v3 to dump the full context of what is used to build the container including the Containerfile. I'm doing that with gitlab-ci to automate building new images regularly but you could do it manually just to dump the containerfile and compare it to the last one you had.

[gendergap]

That is exactly what I was looking for without knowing the tools. Thank you very much @seadoox!