Flex exists to make paying rent work the way real life actually works — smoothing out cash flow, helping renters avoid late fees, and letting them build credit instead of falling behind. As a Staff Backend Engineer, you’ll design, build, and scale the services and integrations behind Payment, Billing, Identity, and partner integrations that keep rent moving on time for renters every month — setting the long-term technical vision and architecture for the systems you own, leading scoping, design, and implementation across teams, driving your own production rollouts to completion with minimal oversight, and working closely with product, design, and engineering peers to solve renters’ most pressing problems in small, frequent iterations rather than big, risky releases. You’ll also raise the bar for the engineers around you, mentoring peers and driving consistency and best practices across the org.