Today I will modify the matrix server (available at https://chat.ondergrond.org) so that usernames there end with ondergrond.org instead of matrix.ondergrond.org. You will need to create your accounts again when I'm done! Since only a couple of people are using it right now it shouldn't be a big deal :P
This is one of the first steps towards having a unified 'ondergrond account' where your name is consistent across multiple services, instead of having multiple separate accounts!
@f0x yeah that's the plan, doesn't seem to be a way to migrate per se, so I'll add you again when it's finished so we can keep chatting :)