I did think it was somewhat of a long-shot. 
I saw ‘api reference’ and thought I’d chance it.
I think my ridiculously wide-of-the-mark answer may have already revealed my inexperience in this area, but (at the risk of doing exactly the same thing again 
) I think there are some good general pointers in the Beginner's guide to developing Discourse Themes if you’ve not seen that already?
But hopefully someone more knowledgable will turn up and be able to offer something actually helpful. 