Yeah. JS might help in this regard, but I guess I am hoping for an system where there isn't the same divide between coding environment and platform being coded

Yeah. JS might help in this regard, but I guess I am hoping for an system where there isn't the same divide between coding environment and platform being coded for. If you could build excel (or similar) _within_ lighttable - and still allow all sorts of live code testing - that would be a real leap to me.