SYMMIO is a decentralized derivatives protocol that introduces the concept of symmetric contracts, a new trading primitive that facilitates on-chain, over-the-counter derivatives trading. SYMMIO is built on an intent-centric architecture. When both parties submit collateral, the requester (Party A) and the responder (Party B) are matched and the transaction is executed, locking them into an orphaned, symmetric transaction. SYMMIO itself does not provide any trading or facilitate any derivatives trading; SYMMIO only provides the infrastructure for peer-to-peer bilateral matching, which third-party providers can use to build fully functional on-chain derivatives exchanges.