This kid was a programming prodigy - he was fifteen, and already capable of doing stuff like that... mind you, that project has been going on for years already, and a playable version was out years ago, when he was only like twelve or thirteen.
RIP, man, you've earned my respect. For a while I actually wished this was some kind of sick joke, but... looks like it's for real.
Poor guy. A great undertaking that he was doing... may he rest in peace.