G'day Joey!
I'm in the process of deploying Docker infrastructure via Propellor on both Jessie and Stretch and I've come to discover that Docker.io did not make it into Stretch:
So the below from Docker.hs will fail beyond Jessie:
installed :: Property DebianLike
installed = Apt.installed ["docker.io"]
Before I embarked on my own path to re-implement the above (probably based on How to install Docker engine on Debian 9 Stretch Linux), I thought I'd see what you thought might be the way to resolve this, so that my work could be contributed upstream (if suitable).
Thanks!
Apparently the Debian way to install docker will be from backports. https://bugs.debian.org/cgi-bin/bugreport.cgi?att=3;bug=781554;msg=9
Note that I'm no longer using any docker Properties myself, so propellor users who are will need to send patches..