How would you go about copying something you installed from apt in a build container?
Say `apt install build-essential libvips` from the OP, it's not obvious to me what files libvps is adding. I suppose there's probably an incantation for that? What about something that installs a binary? Seems like a pain to chase down everything that's arbitrarily touched by an apt install, am I missing some tooling that would tame that pain?
It's a pain, hence for apt as long as it's the same packages, just cleaning is probably fine. But e.g. build-essential is there to handle building extensions pulled in by gems, and that isn't necessary in the actual container if you bring over the files built and/or installed by rubgygems, so the set of packages can be quite different.
Run "dpkg -L libvips" to find the files belonging to that package. This doesn't cover what's changed in post install hooks, but for most docker-relevant things, it's good enough.
Say `apt install build-essential libvips` from the OP, it's not obvious to me what files libvps is adding. I suppose there's probably an incantation for that? What about something that installs a binary? Seems like a pain to chase down everything that's arbitrarily touched by an apt install, am I missing some tooling that would tame that pain?