G'day VinsWorldcom,

++ That's very interesting.

I haven't done this previously and, from the first few links I posted in the OP, it seemed like creating .gitlab-ci.yml first was the way to go. I'd planned to deal with the container aspects later. Perhaps I'm approaching this from the wrong end.

Yes, I had planned on multiple steps as in the "DBD::Mock: .gitlab-ci.yml" (mentioned in the OP).

As those steps are all going to be identical, except for the image: parts, it would be preferable if that could be put in a loop; along the lines of:

for my $tag (qw{5.16 5.18 ... 5.32 5.34 latest}) {
    ...
    image: perl:$tag
    ...
}
[download]

I'll look for some way to do that; if not, then it's the WET (non-DRY) approach.