Quack enables easy, safe and secure atomic swaps of Nxt-based Assets and Currencies. With Quack, Nxt users can now directly exchange Assets, Currencies or NXT with no counterparty risk. Quack swaps/exchanges are implemented on the Nxt blockchain using Phased Transactions. Use Quack to directly exchange Asset<>Asset, Asset<>Currency, or Currency<>Currency, swapping them directly without the need to convert to NXT.