Zero-knowledge for all Ether-Huffers

“Loopring is an open protocol for building decentralized exchanges. Loopring operates as a public set of smart contracts responsible for trade and settlement, with an off-chain group of actors aggregating and communicating orders. The protocol is free, extensible, and serves as a standardized building block for decentralized applications (dApps) that incorporate exchange functionality.” https://crypto-economy.com/loopring-protocol/