Provable Object Data (POD) is a format any app to easily sign data and make ZK proofs without manual circuit writing or trusted setup. Proofs are described in a simple configuration language, then compiled to a family of General Purpose Circuits (GPCs). POD tech is used in Zupass and available as open-source libraries. We’ll dive into the cryptography behind PODs, and what makes them suited to ZK proofs. We’ll also cover the modular design which makes GPC circuits highly configurable.