I could get some of this work uploaded to Debian, but ultimately I was a bit stuck on how to solve the circular dependencies that plague the Docker package. I joined the Debian Go Packaging Team and I started to work on the many, many Docker dependencies that needed to be updated in order to update the Docker package itself. I personally started to work on that early in 2018. Let me give you a very rough summary of how things came to be. Another interesting fact is that, version-wise, the package is moving from 1.13.1 from early 2017 to version 18.03 from March 2018: that's a one-year leap forward. The most striking fact about this change: it's the first time in two years that docker.io has migrated to 'testing'. This is good news for Debian users, as before that the package was more or less abandoned in 'unstable', and the future was uncertain.

Quickly afterwards, the package moved to Debian Testing. Last week, a new version of docker.io, the Docker package provided by Debian, was uploaded to Debian Unstable.

Docker debian