[djsumdog]

I don't think Alpine uses systemd, so there's that.

I attempted Alpine for my router, but at the time there was no UEFI support (grub2-efi was in the unstable tree). That made me turn to Void Linux, which is totally worth checking out. I use it on my current x86 based router:

http://penguindreams.org/blog/building-a-thin-itx-router/

edit: sorry didn't read you comment entirely; init system doesn't make a difference for a docker base :-P