Senior Software Engineer - Cards

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.

Responsibilities

Lead projects from idea to tech spec to implementation to launch; Learn how debit and credit cards work (authorization, clearing, settlement, disputes) and apply that knowledge daily; Build features across the stack, from card experiences customers use to backend systems that move money; Help keep operations excellent, including observability of systems; Mentor other engineers and raise engineering quality through design reviews, code reviews, and collaboration; Work with product, design, operations, risk, compliance, sales, and other teams

Requirements

Strong full-stack experience; Product mindset; Systems thinking; Knack for getting things across the line; Experience making architectural decisions on complex systems, with the ability to explain reasoning and trade-offs; Excited to put new features in customers' hands and care about keeping existing ones working; Care about correctness in systems where failure has real financial consequences; Communicate clearly and handle ambiguity well; Enjoy mentoring others; Comfortable with the tech stack (Haskell and TypeScript) or ready to learn

Nice to have

Experience in fintech; Experience in payments; Experience in card issuing

Benefits

Equity (stock options/RSUs)