I've been considering to make a website with something else than PHP. Not that I hate PHP, but to experiment some stuff with Flask or something else.
Hey that's cool! I always had a weird curiosity about using Ruby for web development. I bet you'll make some cool shit!
How on Earth do you do that ? O.o' This sounds great !
Basically you set gpg-agent to handle SSH authentication, then tell gpg-agent which key(s) to use for SSH auth. This is a good guide: https://github.com/drduh/YubiKey-Guide#ssh
If you set it up correctly, you can then gpg --export-ssh-key [id] to get your public ssh key that you place in .ssh/authorized_keys on whatever remote server. And your ability to ssh in goes wherever your gpg key goes, which makes it great for a yubikey.
I need to get a yubikey next so I can just store my pgp key on that instead of relying on manually backing it up.
Oh, by the way Matthias, it looks like your PGP signature was inline. If you use mutt or neomutt, it will automagically be an attachment.