Yes, it's a new bytecode format and some application-layer stuff to go along with it (like some networking tools). This is almost impossible to determine becaus

Yes, it's a new bytecode format and some application-layer stuff to go along with it (like some networking tools). This is almost impossible to determine because they intentionally made this as obscure as possible. A relatively clear explanation of what Urbit is and why they made it so intentionally confusing is available on the UR blog. I don't remember the title; something about computers in 2020.