Senior Software Engineer, Affirm Bank

Affirm is reinventing credit to make it more honest and friendly, giving consumers the flexibility to buy now and pay later without any hidden fees or compounding interest.

About the Role

Affirm is building its own bank — and this role sits in the engineering team that runs it. We're looking for a Senior Software Engineer to join a deliberately small, AI-native team that owns the systems behind Affirm's bank: vendor-integrated banking infrastructure, durable workflows, data platform, and the operational tooling that holds it all together. You'll work alongside other senior engineers, with direct exposure to senior bank and Affirm leadership, to launch the bank's deposit product, drive loan originations through the bank entity, and bring card issuing online in time.

This is a rare opportunity to shape a new business from its very first systems — a startup-like build inside an established company. You'll be one of the first engineers on Affirm's bank, moving with the speed, autonomy, and ownership of an early-stage team while leveraging Affirm's brand, distribution, and consumer reach. The team is small and AI-native, the surface area is broad, and the work meaningfully matters — every system you ship serves real customers under a real bank charter. The systems you build and the standards you set will directly determine what the bank becomes.

What You'll Do

• Own bank systems end-to-end. Design, build, integrate, operate, and own incident response for the bank's core technical surfaces: cloud infrastructure, data platform, durable workflow orchestration, core banking configuration, CI/CD, networking, and the Bank ↔ Affirm Inc integration. Generalist breadth is expected.
• Be a force multiplier on a small team. Set and improve code review and design standards, lift the bar on examiner-readable documentation, and make the team you join more effective than the team you found. Every Senior IC on this team has outsized influence on what gets built and how.
• Ship AI-first. Lean on AI tools and agentic workflows as a multiplier for code, design review, runbook generation, and operations. Push yourself and your teammates on what an AI-leveraged team can deliver.
• Own vendor relationships. Carry one or more of the bank's third-party vendor relationships end-to-end — integration, operations, escalation, and audit. The bank's tech stack is intentionally vendor-leveraged, and ownership of those relationships is an engineering responsibility.
• Build for examiners. Partner with Legal, Compliance, Risk, and Internal Audit to factor in compliance from day one. Write decisions, designs, and runbooks to a standard that holds up under examiner and audit review.