Unfortunately there’s little bbPress documentation right for developers. It’s very much like WordPress however, just different hooks (do_action, do_filter).
There’s no official list of functions but some people have generated xrefs for it, example:
http://phpxref.ftwr.co.uk/bbpress/nav.html?index.html
(unofficial)
I keep a database reference here:
http://bbshowcase.org/reference/
but it’s a little out of date for 1.0 alpha
To upload your plugin into the extend area, first you have to request a “slot” under Extend->add your plugin
https://bbpress.org/plugins/requests/
Then you’ll get an email when it’s approved in a few days (mdawaffe is distracted these days, it can take 1-5 days on average) Then you need to learn how to use SVN to upload your files into the system.
The steps are the same as for WordPress and here’s a good guide:
http://www.binarymoon.co.uk/2008/01/wordpress-plugin-subversion-guide/
only the svn url is different
https://plugins-svn.bbpress.org/
