Senior Software Engineer - Cards

As the story goes, in 1949 Frank McNamara finished dinner at a New York restaurant and found he'd left his wallet in another suit. His fix was a card that let members eat now and pay later. That card became Diners Club, widely credited as the first multipurpose charge card. It was a piece of cardboard and a promise: the restaurant trusted the card, the card trusted the member, and someone had to make sure the money actually moved. More than seventy-five years later, the promise hasn't changed, but the machinery has. When a Mercury customer taps their card, the request goes from the merchant's terminal through an acquirer and a card network to us. In a fraction of a second, we check the balance, apply the customer's spend controls, screen for fraud and say yes or no. After that comes clearing, settlement, disputes and reporting, and every cent has to reconcile. Cards are the way Mercury customers spend money. The Cards Integration team owns the whole Mercury card, not just the swipe: issuance, physical card shipping, spend controls, lifecycle management, authorization, money movement, settlement and reporting, and the infrastructure underneath. We're a full-stack team, and our job is to make the Mercury Debit and IO cards reliable, correct, useful, and innovative. We're looking for a Senior Software Engineer who thinks deeply about systems architecture, cares about the customer experience, and will dive into any problem to move the team forward. We value high ownership, workin