tl;dr - Scroll to the bottom for the fix, if you’re having the problem, thanks to Garett L Ward for submitting the fix to me over email!
tl;dr - My setup of Docker on Arch Linux is having some issues, around
docker0 not properly holding on to it’s IPV4 addresses (listed as
ip addr output). I originally though it was a problem with Alpine CDNs, but it was actually
docker0 throwing up repeatedly. Short term work around I’ve found is to just create the missing link again, w/
sudo ip addr add 172.17.0.1/16 dev docker0.