> and it "just worked" For me, it frequently didn't. Sure, nginx will work out of the box, but I've had some difficult Apache installs, and less mature softwar

> and it "just worked" For me, it frequently didn't. Sure, nginx will work out of the box, but I've had some difficult Apache installs, and less mature software? Often a dependency/configuration nightmare, and then, sometimes, it still would die with an opaque error message. And then something breaks and getting to a clean slate can be challenging. That's one of the huge upsides of Docker for me: Stuff finally "just works" on my machines, too! And it actually "just works" on others' machines as well, which it has all along as they tell me, but it even does so when I'm watching. Amazing, really. I think the config situation has improved as well – the most frequently used configuration options usually can be passed in as environment variables, so I don't have to pin things to non-default values just because the config file I copied and edited had that default value in its config at that particular version, only to break five versions later – neat. If I do need a config file, I keep it in git and bind-mount it in – the location is usually easy to find (e.g. in the docker run one-liner on the DockerHub page). Image sizes can be crazy, that part needs work, many people don't write space-efficient Dockerfiles. I try to use alpine or scratch images where possible, that makes the problem quite manageable; and, frankly, the amounts of network, storage and ram needed for the overhead of an alpine image are a very fair bargain for the time and headspace I gain by being able to treat applications as a way darker-gray box than otherwise.