Once the buyer requests a valid Order = {Token, Amount, Wallet, Price} by our front-end, we define it as a Contract to be executed, and our system generates a QR-Code for a BRL payment over PIX with a random UUID. Probably, the most important design choice for this solution is based on a new Brazilian Fintech digital Bank which has an unprecedented Open Banking API that enables Moeda to observe when a payment is done to our Agents, detecting a valid UUID:order paid on their BRL Bank history over an API.