Principal Security Engineer, Infrastructure Security

About the Team Security is at the foundation of OpenAI’s mission to ensure that artificial general intelligence benefits all of humanity. The Security team protects OpenAI’s technology, people, and products. We are technical in what we build but are operational in how we do our work, and are committed to supporting all products and research at OpenAI. Our Security team tenets include: prioritizing for impact, enabling researchers, preparing for future transformative technologies, and engaging a robust security culture. About the Role OpenAI is seeking a Principal Security Engineer to join our Infrastructure Security (InfraSec) team. InfraSec protects the foundations of OpenAI’s research and production environments, spanning GPU supercomputing clusters, multi-cloud infrastructure, datacenters, networking, storage, and the critical services that power our frontier AI models. Our charter includes securing everything from bare-metal hardware and firmware, to Kubernetes clusters and service meshes, to data storage and access pathways for highly sensitive model weights and user data. As a principal engineer, you will set technical direction and drive execution on high-impact infrastructure security programs, partnering across various orgs at OpenAI to deliver durable controls that raise the security bar at OpenAI scale. In this role, you will: Own end-to-end security outcomes for one or more critical infrastructure areas, including multi-quarter strategy, roadmap, and delivery. Design and build security controls across diverse layers (e.g., physical hardware, firmware/BMC, OS, Kubernetes, networks, and CI/CD) to defend against sophisticated adversaries and insider threats. Lead cross-functional programs to deploy security enhancements and control changes across broad-scale infrastructure, balancing security guarantees with reliability and velocity. Take a generalist approach to building security controls, balancing a mix of security expertise and broad technical skillsets to adapt to evolving challenges. Lead and/or drive threat modeling and design reviews for major infrastructure changes, ensuring strong security foundations and operational excellence. Mentor and level up engineers across InfraSec and partner teams, contributing to a strong security culture through guidance, reviews, and technical leadership. You will thrive in this role if you have: Deep understanding of security principles, best practices, and common vulnerabilities, including strong security judgment under ambiguity A proactive mindset, with the ability to identify and address security gaps or inefficiencies through automation and tooling. Expertise and curiosity about using frontier models and agents to effectively solve security challenges. A track record of leading large, cross-org initiatives from concept to rollout, including navigating tradeoffs, driving alignment, and delivering measurable risk reduction. Deep expertise in the security of cloud platforms (e.g., Amazon AWS, M