To the surprise of absolutely nobody, two "devops-y" programs written in Node.js and in Go do not understand IPv6 only domain names.
Ihis is annoying, because I wanted all of the internal network for the bsd.network instance to use only IPv6. Have IPv4 only at the edge, for the web site and to push and pull statuses from other instances.
Oh well, I'll just use non-routed IPs for it.