Principal Application Security Engineer

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.

Upstart’s Application Security team is passionate in bringing progressive approaches in securing our products. We believe that security should empower innovation, move at the speed of business, and have safety by design as core principles. Our team’s mission is to ensure the safety of our core product platforms, enterprise, and manage threats to Upstart. We approach our efforts through automation, strong collaboration with our partner teams, and maintaining a positive experience for Upstarters.

As the Principle Application Security Engineer at Upstart, you will be expected to lead cross-functional and cross-organizational discussions and outcomes around threat modeling, application and infrastructure security. You will be expected to deeply understand the business verticals and product needs and influence them to build highly secure systems and platforms. You will have a direct hand in shaping the strategic security posture and roadmap for Upstart and should be a well-rounded technologist and security practitioner.

• Define and drive Upstart’s application security strategy, aligning secure‑by‑design principles with business priorities, regulatory expectations, and our AI‑driven product roadmap.
• Lead cross‑functional security architecture reviews for critical initiatives, influencing engineering, platform, data, and infrastructure decisions to reduce systemic risk early in the SDLC.
• Establish and scale a robust threat modeling program for high‑risk systems, including customer‑facing applications, lending workflows, and ML/AI pipelines, translating findings into durable engineering standards and controls.
• Design and standardize application security guardrails across the SDLC, including secure coding practices, automated testing (SAST/DAST/SCA), CI/CD protections, and secrets management.
• Partner with Infrastructure and Cloud teams to strengthen the security posture of cloud‑native and distributed systems, ensuring defense‑in‑depth across application and infrastructure layers.
• Identify and reduce internal and external attack surface through automation and platform‑level solutions, prioritizing long‑term risk reduction over point‑in‑time remediation.
• Serve as a senior technical authority during high‑severity incidents, driving root cause analysis and durable architectural improvements.
• Elevate security maturity across the organization by mentoring engineers, influencing leadership through clear risk metrics, and fostering a culture where security enables innovation.

Minimum requirements:

• 6+…