Comment by chrisjharris

I also am quite neurotic about version control, updates etc and if you're prepared to climb up a fairly steep learning curve, I'd recommend Nix/NixOS. It's a much more robust and comprehensive solution than Docker. Docker is not as good a technology as it should be in this use case, and it does stuff like cacheing CMD instructions in the Dockerfile based on their value as a string (rather than the result of the command). This can and does lead to Docker images changing between builds even when the Dockerfile itself has not changed.