If you meet a New Contributor who wants to code for SUMO, we have a wiki page that has all the details on how to help out with Kitsune (that’s the name of the platform): https://wiki.mozilla.org/Webdev/GetInvolved/support.mozilla.org
The main contact person for Kitsune’s development is Ricky. You can find his details on the page above.
If the new contributors wants to code in a different area of Mozilla’s activity, please send them to the MDN: http://developer.mozilla.org/
Questions? Comments? You know what to do