Thanks for all your answers! I will check some of the alternatives to duckdns.

I have a domain… but I think DynDNS is not always available for every domain or by every domain seller?

In my case, there is no IP change. However, the TTL of entries seems to be 60 seconds and when Cloudfare/Google asks for the new A record, it sometimes fails. I am getting this error message from Cloudfare when I try to solve host.sub-domain.duckdns.org

EDE: 22 (No Reachable Authority): (time limit exceeded)

rm -rf /var

I don’t know what I was thinking on to type it 😅

AFAIK immich organize photos with albums not in folders. So, If i move from immich to another software (librephotos, photoprism…), the new software is aware of albums? I am worried on organizing my photos every time I change of photo management application.

this is more or less my current workflow but i feel that is quite difficult to use/find photos in my android phone due to the lack of one android app.

Yes, you explain better :-) The idea is that shell.nix is my development environment so I would like to use that shell.nix to interactive shells (nix-shell) and to run scripts (non-interactive use). I understand I could use a nix-shell shebang in every script, but that requires maintenance (when I modify the shell.nix file, modify the shellbang of all my scripts) and it is prune to errors (for example, modify the shell.nix and forget to modify the shebang of my scripts).

(I am the author of the comment in Reddit) AFAIK there is no instance of lemmy in fosstodon.org and there is no FOSS-only-purpose server in Lemmy.

I agree perhaps lemmy.world server is one of the best options to locate the community due the size (size is important in the fediverse because higher servers are supposed less tending to disappear or to have funding problems) (https://lemmy.world/post/579472) and as @simonmic@lemmy.world said it includes the lemmy word. However, so far, there is no way to migrate one community from one lemmy server to another one and the only solution would be to create a new community in a new server and remove this one to avoid confusion (there are few posts so I think is a good time to do it).