Senior Software Engineer, Identity Platform

About Upstart At Upstart, we’re united by a mission that matters: to radically reduce the cost and complexity of borrowing for all Americans. Every day, we bring creativity, experimentation, and advanced AI to reshape access to credit, helping millions move forward financially with clarity and confidence. As the leading AI lending marketplace, we partner with banks and credit unions to expand access to affordable credit through technology that’s both radically intelligent and deeply human. Our platform runs over one million predictions per borrower using more than 1,800 signals, powering smarter, fairer decisions for millions of customers. But the numbers only hint at the impact. Every idea, every voice, and every contribution moves us closer to a world where credit never stands between people and their financial progress. We’re proudly digital-first, giving most Upstarters the flexibility to do their best work from wherever they thrive, alongside teammates across 80+ cities in the US and Canada. Digital-first doesn’t mean distant. We’re intentional about in-person connection through team onsites, planning sessions, and moments that spark creativity and trust. And whether you choose to work primarily from home or collaborate in-person from one of our offices in Columbus, Austin, the Bay Area, or New York City (opening Summer 2026), you’ll have the support to work in the way that works best for you. If you’re energized by tackling meaningful problems, excited to innovate with purpose, and motivated by work that truly matters, we’d love to hear from you. The Team:  At Upstart, the Identity and Experimentation Platform Team plays a pivotal role in shaping the security and accessibility of our cutting-edge lending products, including Personal Loans, Auto Loans, and Home Loans. We are responsible for creating, securing, and managing borrower and partner identities, ensuring a seamless and secure experience at every touchpoint. As part of our team, you’ll work on the Authentication, Authorization and Experimentation Platform, driving both backend security and frontend user experiences. Our mission is to enable frictionless, secure authentication while safeguarding sensitive data from unauthorized access.If you’re passionate about building scalable security solutions and delivering intuitive user experiences, come be a part of a team that makes financial access more accessible, safer, smarter, and seamless for everyone! As a Senior Software Engineer on Upstart’s Identity Platform Team, you’ll play a critical role in building and securing our authentication, authorization and experimentation systems. You will be responsible for ensuring that borrowers and partners experience a seamless, secure, and scalable identity framework across our lending products, including Personal Loans, Auto Loans, and Home Loans.You’ll work closely with vertical Engineering, Product, and Security teams to develop and experiment solutions that enhance security, improve authentication flows, and drive innovation in Identity and Access Management (IAM) and Experimentation spaces. This role is ideal for someone who enjoys solving complex technical challenges, values clean and scalable architecture, and is eager to make a significant impact on a high-visibility platform. How you’ll make an impact Design, develop, and optimize secure and scalable authentication and authorization systems. Collaborate with cross-functional teams to improve Identity and Access Management (IAM) capabilities, including OAuth, OpenID Connect, MFA, and SSO. Partner with Security teams to enhance security policies and standards, ensuring protection against threats and unauthorized access. Improve Experimentation platform and Lifecycle across the Upstart Network Inc Products. Drive best engineering practices for clean, maintainable, and efficient code. Participate in architectural discussions, helping to shape the long-term vision of Identity Platform. Mentor and collaborate with other engineers to elevate the team’s technical skills and knowledge. Work on high impact initiatives that solve for making credit accessible to everyone. Minimum Qualifications  Bachelor’s degree in Computer Science, Engineering, or Mathematics, or a related field (or its equivalent) + 4 years of experience Strong proficiency in backend technologies (e.g., Kotlin, Java, Ruby, C#). Hands-on experience with authentication and authorization protocols (OAuth 2.0, OpenID Connect, SAML). Experience building scalable APIs using containerization technologies like Docker and Kubernetes. Understanding of security principles, including encryption, token-based authentication, and identity federation. Strong problem-solving and debugging skills, with an emphasis on performance optimization. Ability to balance the needs of the business with engineering best practices and security considerations. Passion for clean code, architecture, and continuous improvement of engineering processes. Experience with AI Coding tools such as Cursor, Claude Code etc. Excellent communication skills – able to translate complex technical concepts for a variety of stakeholders Preferred Qualifications Experience working with IAM platforms and security services. Knowledge of A/B testing, gRPC, and DevOps practices. Experience with Keycloak, NextJS, and Ruby is a plus. Proven ability to influence technical direction without direct authority. Strong product and analytical mindset, capable of making trade-offs between risk, ROI, and performance. Experience working at companies experiencing rapid growth and scaling challenges. Strong sense of ownership and accountability for the quality and timely delivery of work Ability to influence and lead without direct authority Position location This role is available in the following locations: Remote   Travel requirements As a digital first company, the majority of your work can be accomplishe