How to develop xbox indie and xna games?

I was thinking about working on an indie game for the Xbox 360 (Xbox one indie game later) but how can I code for an indie game with unity or is it not supported?
Right now, I am using the sunburn sdk which is not too bad and has an editor that specifically supports windows, windows phone, and Xbox with xna support.
If anyone knows a method to extend unity to support xna I’ll accept that as an answer too.

Unity cannot export to a xna project.

It’s core engine is written in c++.