Well, Docker has an API and its own file format (the Dockerfile), I constantly have to look up Docker switches as it's not a tool I use every day and it's not at all intuitive, and I'm still unclear why people love this layered/stack image approach given how unbelievably slow it makes everything. Apps that would once have been a 50mb tarball are now routinely a gigabyte of downloads, perhaps because whatever random version of Ubuntu I downloaded previously is now slightly different? Who knows.

There is, frankly, a lot of appeal to me in a simple INI file that starts up something I unzipped.