Senior Software Engineer

At Affirm , we exist for the moments that matter—giving people a clear, predictable way to pay over time, with no hidden fees, no surprises, and no tradeoffs on what matters most.

The Card Loan Platform team builds the high-throughput decision engine at the heart of Affirm ’s card products. Unlike traditional cards, every pay-later transaction is backed by its own unique loan, and our system is the "invisible piping" that makes this complex model work at scale. Every swipe triggers our platform to solve a hard problem in milliseconds: matching messy, fragmented payment network data to the correct loan to drive real-time approvals, origination, and refunds.

As Affirm experiences explosive growth, our team's contributions are a key enabler. This isn't just another backend role; you'll be building the "financial brain" for our flagship card products, with your work on the critical path for every single swipe. We're tackling a unique, high-stakes distributed systems challenge that demands exceptional correctness and massive scale. You will partner closely with product, data science, and engineering teams to design and build the future of our industry-leading money movement platform.