I know quite a few people are following along with HH verbatim, but I've enjoyed working with the concepts in my own game. I haven't copied any source directly, but I've borrowed heavily. The game itself bears no resemblance to HH. What does the license / Casey have to say about posting "inspired-by" works to github and here?
You can mail me at [email protected] if you'd like to do something like that. Mostly it depends on how close it is to the original. Assuming it's sufficiently different it should not be a problem.