Principal Security Engineer

Forward-Deployed Security within CISO Leadership is responsible for bootstrapping and maturing security programs and addressing threats faced by Microsoft divisions with emerging, non-traditional-enterprise technologies. We work where the problems are least standardized and the stakes are real: new products, fast-moving platforms, uneven security maturity and teams that need practical help building an architecture that works for them - not abstract guidance and frameworks. We land, understand the environment, build roadmaps, develop recon and exposure tooling, and stay involved to land security improvements until the problem space is stable and an operational team is ready to stand on its own. We are looking for a Principal Security Engineer who combines deep, technical security expertise with a builder's mindset, end-to-end ownership, and insight into what it takes to build a platform. This role sits in the Security Assurance Family, but the work is broader than classic assurance. You will assess complex systems, develop the path to meaningful risk reduction, build defensible architectures with real tools and automation, and work directly with product-line teams to get fixes and secure patterns adopted and validated. This is a role for someone who likes ambiguous problems, learns by doing, and measures success by durable improvement rather than by findings written down.

Lead deep technical security reviews of products, services, infrastructure, and emerging technologies using AI-enabled methods including architecture analysis, threat modeling, adversarial testing, source review, telemetry, and data analysis. Turn review outcomes into prioritized security roadmaps with clear tradeoffs, practical milestones, and measurable risk-reduction goals. Build and maintain security tools, automation, prototypes, and reusable engineering patterns that teams adopt in real workflows. Partner directly with product and research teams to design, debug, implement, and validate security improvements, staying engaged through root-cause resolution rather than stopping at recommendations. Integrate automated security checks, guardrails, and secure defaults into engineering systems so successful one-off work becomes scalable capability. Use threat intelligence, hunting techniques, telemetry, and incident learning to identify emerging attack paths and convert them into detections, controls, and engineering priorities.

Required/Minimum Qualifications Doctorate in Statistics, Mathematics, Computer Science, or related field AND 5+ years experience in software development lifecycle, large-scale computing, threat modeling, cyber security, anomaly detection, Security Operations Center (SOC) detection, threat analytics, security incident and event management (SIEM), information technology (IT), or operations incident response OR Master's Degree in Statistics, Mathematics, Computer Science, or related field AND 6+ years experience in software development lifecycle, large-scale computing, threat modeling, cyber security, anomaly detection, Security Operations Center (SOC) detection, threat analytics, security incident and event management (SIEM), information technology (IT), or operations incident response OR Bachelor's Degree in Statistics, Mathematics, Computer Science, or related field AND 8+ years experience in software development lifecycle, large-scale computing, threat modeling, cyber security, anomaly detection, Security Operations Center (SOC) detection, threat analytics, security incident and event management (SIEM), information technology (IT), or operations incident response OR equivalent experience. Additional or Preferred Qualifications  Experience owning complex, multidisciplinary, multi-organization security problems from initial scoping through technical resolution and validated improvement. Experience building and maintaining security tools, automation, or internal security capabilities used by real