I wrote https://fly.io/ruby-dispatch/rails-on-docker-without-docker/ to share observations I’ve made and questions I’ve gotten about Docker, Kamal, and Fly.io. The biggest surprise to me is how some Rails devs don’t want to take time away from building their apps to install, learn, and figure out Docker, so I make a case for how Fly.io can gradually introduce Docker without slowing down velocity.