Email: [email protected]
This is the easiest way to contact me and usually results in the quickest reply!
I'm fairly active on Twitter—even though I don't post a great deal—so if you @ or DM me then you're likely to get a fairly swift response (though not as fast as email).
Signal is an awesome and secure instant messaging service that works well both on mobile (iOS and Android) as well as on your computer. Also, in case you didn't know, WhatsApp uses the Signal Protocol.
Here you can find my public key as well as a number of identity proofs. Feel free to use what is here in order to contact me, securely.