A marketing-speak filtered out version of this announcement: You will be able to assemble your own docker engine by stripping out components you don't need (that have until now been shipped in a single docker binary) and keeping the ones you do. This is like assembling PCs, for docker.

I think this was mainly intended as an answer to the criticism docker has been receiving (by kubernetes maintainers and others) ever since they decided to ship swarm with docker. I think this move is great as it goes a step further and allows you to swap out build systems, volume mgmnt too. Even though I did not mind docker shipping with swarm, others in the community were, and this shows docker listened, which is great.

EDIT: grammar fix