Keybase.io is awesome!
But the problem was, you could not really use it for email, nor sign your Github commits, as keybase only entered a non existing email into the public key (yourname@keybase.io). But - you can change that :). You'll need to have GNU PGP / GPG installed.
Download Private and Public Key from Keybase.io (edit Button next to Key on Profile, Export my Private Key, Key Checksum for Export of Public Key)
gpg --allow-secret-key-import --import keybase-private.key gpg --import keybase-public.key gpg --edit-key myname@keybase.io
then in the gnupg ‘shell’:
gpg> adduid Real name: Full Name Email address: myname@mymail.com Comment: <canbeleftempty,just enter>
You'll need to enter your Key to allow the changes.
Stay in gpg shell and do following to trust yourself (maybe not necessary):
uid myname@mymail.com trust 5 y save
Export your newly generated public key:
gpg --armor --export myname@mymail.com
Upload to Github for Sign (New GPG key): https://github.com/settings/keys
Upload Public Key to Keybase: https://keybase.io/myname (edit, Update my key)
You can sign now on Github with:
git commit -S -m "signed commit"
Infos taken from:
http://superuser.com/questions/293184/one-gnupg-pgp-key-pair-two-emails
http://stackoverflow.com/questions/22136029/how-to-display-gpg-key-details-without-importing-it