You're right in the absolute form, but I've yet to see a Dockerfile where (with a little thinking and elbow grease) I couldn't "easily" port it or update it, ev

You're right in the absolute form, but I've yet to see a Dockerfile where (with a little thinking and elbow grease) I couldn't "easily" port it or update it, even after years. It's basically the best and easiest "I am documenting how it works now" thing without any arcane "works on my machine" quirks I have yet found. So I'm still agreeing here that it's a very good approximation of this idea. Real reproducability is miles better, but usually cannot be formulated in a ~20 line single file "recipe". (and before anyone mentions Nix.. no, there's so much inherent complexity involved, that doesn't count like "apt-get install docker && docker build ."