Staff Software Engineer, FinPlatform Backend

<div class="content-intro"><p>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?</p></div><h1><span style="font-size: 12pt;"><strong>Overview </strong></span></h1> <p>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?</p> <h3 data-start="1120" data-end="1144"><strong data-start="1124" data-end="1142">About the Role</strong></h3> <p data-start="1145" data-end="1506">Flex is looking for a Staff Software Engineer to join our core platform team. We want engineers with ideas (because they’ll definitely be heard on our small and tight-knit team) and ambition! Successful devs will feel comfortable in a startup environment and will be happy to work in a remote-first team with a lot of independence. As a Staff Engineer at Flex, you’ll help set technical direction and shape the long-term architecture of our backend services while still being hands-on with coding and delivery. You will collaborate across engineering, product, design, and other stakeholders to ensure scalable, reliable, and impactful systems that power consumer experiences, partner integrations, and our core business platforms. You’ll also play a critical role in mentoring engineers, elevating technical standards, and ensuring the success of projects end-to-end.</p> <p><strong>Our Engineering Teams</strong><strong><br></strong></p> <ul> <li><strong>Consumer Engineering:</strong> Builds the APIs and backend systems powering Flex’s main consumer-facing products. This team focuses on delivering scalable services for a seamless rent payment experience through our mobile and web apps.<br><br></li> <li><strong>Partner Integrations Engineering:</strong> Owns the backend services and integrations that connect Flex to financial partners and payment networks, ensuring reliable, secure payment flows and partner-facing experiences.<br><br></li> <li><strong>Core Platform Engineering:</strong> Maintains the backend systems and infrastructure supporting all business features, including Payments, Billing, Identity, and Partner Integrations, ensuring Flex’s foundation is robust and scalable.<br><br></li> <li><strong>Risk Platform Engineering:</strong> Develops the platforms and APIs that mitigate credit and fraud risk, enhancing customer accessibility while safeguarding against misuse through advanced rules engines, machine learning, and event data systems.</li> </ul> <h3 data-start="2752" data-end="2774"><strong data-start="2756" data-end="2774"><br>What You’ll Do</strong></h3> <ul> <li>Design, implement and maintain our Finance service and internal tooling, including financial reporting, reconciliation/audit process.</li> <li>Design and develop new APIs and functionalities to support large money movements across ... (truncated, view full listing at source)