No, just pseudo-code.
Right now we don't have a lot of real JMAP code. FastMail's implementation technically isn't JMAP. To write JMAP we took our current protocol and filed off a lot of the pointy edges. We're working to update our own implementation, and we're also working on open-source reference servers and clients.
There's a mailing list just starting here:
https://groups.google.com/forum/#!forum/jmap-discuss
You might like to sign up and lurk there. I'll be posting to it soon (maybe tonight) to get the ball rolling on a few things.