That is actually a tradition of most "app-store-first" platforms. I have plenty of experience here with the Nokia/Ovi store.... and "rewrite" is being too generous here. That said, we cannot really compete with a full-time employee working on it. "Rewriting" it back from their version should be considered an option. For me at least it looks easier than writing a store UI. The best source for documentation at this point is pebbled, and the fact that Ubuntu guys decided to rip it off entirely and even Pebble employees themselves are using parts of it now should be kind of proof...