Senior Backend Engineer, Consumer Product
USAEst. $172K – $212K
Posted May 21, 2026
Flex is a growth-stage, NYC headquartered FinTech company that is creating the best rent payment experience. It’s hard to believe that it’s 2026 and paying rent on time is expensive, inflexible, and difficult. We’re here to change that! Flex enables our users to pay rent throughout the month on a schedule that better fits their finances and budget. Our mission is to empower as many renters as possible with flexibility over their most significant recurring expense. After deliberately keeping a stealth profile as we built up unprecedented investor support and an enthusiastic user base, we are looking for motivated individuals to help us keep our mission growing. Will you be a part of the team? About the Role
Flex is on a mission to change the way people pay for the things that matter most — starting with rent. As a Senior Engineer on our Consumer Product Engineering team, you'll be part of the orchestration layer — a small, focused team responsible for the app-friendly APIs that connect our mobile and web apps to Flex's core platform services. You'll design, develop, test, and scale the APIs that sit at the heart of our customer experience, abstracting the complexity of rent payment processing into seamless, reliable interactions for our users. This is a role for a product-minded backend engineer who stays grounded in the experience their code enables. You'll work in close partnership with Product, Design, and Engineering peers to solve our users' most pressing problems around rent payment, shipping changes in an agile cadence that favors small, frequent iterations. You'll lead scoping, design, and implementation for the APIs you own and drive production rollouts to completion with a high degree of independence. Success here looks like building APIs that make complex things feel simple, shipping high-quality features on time, and raising the bar for the engineers around you. You'll bring both technical rigor and genuine product curiosity to a collaborative, fast-moving team that cares deeply about what it builds and who it builds it for.