The best way to reach me is by e-mail at firstname.lastname@example.org.
If you need to send me an encrypted file or message then you can use my GPG key or my Keybase account. If you’re not familiar with how to use GPG/PGP then you can find many good guides and ways to improve your usage online.
However, I’d really recommend you stay away from GPG. If you need to reach me securely then send me an email and I can give you my Signal number.
If IRC is your thing then I can be found as xoebus on freenode.
For everything else, there’s always Twitter.
If you’re trying to verify some software that I’ve written and released then you’re probably looking for one of these signify keys: