

If you only need it to be accessible inside your home, then you just need to run your own DNS. Have your dhcp point at your DNS and your DNS declare itself the master for your domain.
To get full functionality, you’ll probably want to have your registrar point to the public IP you get from your ISP as the domain’s authoritative name server.You should be able to script it to update the registrar when your ISP changes your IP, but that usually happens infrequently enough to do manually. Obviously can’t do that if you’re behind CGNAT.
To get Lets Encrypt certificates, you can do the DNS challenge. If your ISP gives you a (even inconsistent) public IP, you can do fancy ‘views’ with your selfhosted DNS, where it responds with private IPs inside your network and your ISP-given IP outside your network. I have certbot set up to expose my DNS & web server just before it starts its renewal process, then close the firewall after. Once you have the certificate, you can move it to where ever it will actually be used.








That’s just systemd adding a birthdate field to their userdb. Doesn’t require that it be filled out or accurate, and especially doesn’t require it to be validated against a government database. I don’t see it as fundamentally any different from adding a userdb field for favorite color, phone number, or blood type.
Without 3rd party validation, I really don’t see the privacy issue with an age field. Without verification, it is, at worst, one more byte available to hash into a unique identifier, but you can feed that field from /dev/random at every query and poison even that hypothetical.