I have a Samba mount at home (behind NAT, accessible via wireguard VPN), which works very well when accessing my home files when traveling (I travel a lot for work).
The only detail missing from this solution is sharing individual files with friends. I could give them access to my VPN, but that gives them access to everything, not just one thing I want to share. Also not all my friends are that tech savvy to manage connecting to a VPN.
What would be really great is to have a link-generator that punches a hole in the NAT to give them access to specific files. Are there any self-hosted solutions for that?
You can consider using a Pikapods service for this. It’s dead simple to strand up a server when you need one.
https://www.pikapods.com/apps#storage
They have Gokapi and/or PrivateBin for just about a buck per month. You can turn the service on and off whenever you like. Good company to work with, IME, too.