FWIW there are free dynamic DNS services out there. IIRC I'm using Hurricane Electric's for one machine in my house.

Often consumer routers bake in support for notifying DynDNS providers of IP changes, even. (Both my new one and my 6-year-old one had that, I noticed recently.)

(I also bailed on doing that once and ran a custom Jabber bot that would hit whatismyip when asked and reply with it to me. Reinvented DNS poorly? ✅ But DNS scares me way more than chat, so.)

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