Looks good but I have one question. If the docker images are built from docker hub and not from Travis then they will just run the Dockerfile and ignore our Makefile. In that case your changes will do nothing except when we build manually.

Ah, yes indeed. At this point in time the build args would not be passed and the values would be empty in the resulting image.

It seems this can be mitigated through build hooks (https://docs.docker.com/docker-hub/builds/advanced/). Currently have a test build running. Will push the required hook if my change succeeds.

Edit: I should add that this "breaks" build layer caching as the values passed as build arguments will be changing quite often (everytime you make a git commit). So it could be an idea to have just one make build.

Edit2: hook can be tested by running DOCKERFILE_PATH=./Dockerfile IMAGE_NAME=docker-mailserver hooks/build in the root of the project.

No rush or anything, I just want to check that you are not waiting for me on this and/or your other PRs?

It seems we both forgot about this. Let me rebase, wondering about some of the Makefile changes, though.

Right. If you are waiting for me on something, please just leave a comment.

@erik-wramner is not ok 198 checking setup.sh: setup.sh email add and login a known failure?

Yes, it happens every now and then.

OK, after regriggering tests are green. Let's merge.