Senior Software Engineer, Full Stack (Zero to One Labs)

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. Zero To One (ZT1) is Affirm’s 0 -> 1 innovation lab, focused on turning bold ideas into validated new businesses. Operating outside the standard Product and Engineering structure, ZT1 is built for speed, autonomy, and decisive execution. We run fast, hypothesis-driven experiments with a clear goal: prototype quickly, generate real signals, and drive explicit “kill or scale” decisions on high-impact opportunities, with AI as a core enabler across the stack. As an engineer on ZT1, you will work in a small, highly empowered, AI-native team alongside product managers and cross-functional partners, with direct exposure to senior leadership. You will not just build systems, you will help shape experiments, define technical approaches, and influence product direction. Work h