In this talk, we dive into the world of collaborative SNARKs, what they are, the unique challenges they tackle, and what they are used for. We explore how to create private shared state, enabling private on-chain data to stay private while still supporting computations that draw from multiple data owners, all without compromising privacy. We then introduce a oblivious map primitive, a private counterpart of hashmaps, and demonstrate how it can be used to build a fully private on-chain payment solution which hides sender, receiver, balances, and transaction amounts.