ddclient

ddclient is a small Perl client that keeps a domain name pointing at your current public IP address by talking to the update protocol of your dynamic DNS provider. It supports many providers, from DynDNS and No-IP to Cloudflare, Duck DNS and Gandi, and it can learn the external address from a web service, a local command or UPnP.

It is the classic choice for home labs and small servers sitting behind a changing residential IP, and for anyone whose hostname has to survive a router reboot.

Self-hosting keeps the credentials in a configuration file on your own machine, the updates run on your schedule, and there is nothing to subscribe to or renew.