Great move by the docker team. The promise of containers has always been to make the environment that processes live in super lightweight, with a minimum of unn

Great move by the docker team. The promise of containers has always been to make the environment that processes live in super lightweight, with a minimum of unnecessary binaries and permissions. Having a full ubuntu installation per container has been a major hazard to that, as it's required the use of overlays and other tricks to avoid having huge disk overhead per container. Moving to a much lighterweight base image means you need fewer overlays, because you can pay the 5mb cost for days. It also reduces the attack surface by a lot, for much greater security.