Principal Software Engineer

The Applied Sciences Group (ASG) is Microsoft's interdisciplinary research and engineering organization that delivers AI-powered experiences and models across Windows, Microsoft 365, and Copilot, while incubating novel devices, agent platforms, and on-device AI capabilities. We combine full-stack AI, sensing technologies, and hardware/software co-design to reinvent human-computer interaction and enable secure, compliant, high-performance on-device AI at scale. This role focuses on building security-critical biometric identity systems that ground digital interactions in real human presence. The work spans high-assurance identity verification, defense against spoofing and impersonation, and secure operation across cloud- and device-based AI experiences at a global scale. As AI systems become more autonomous, biometric identity is essential for establishing trust and security across platforms. You will architect for these foundational identity and security services, making long-term technical decisions for Microsoft's evolving AI platforms. We are seeking a Principal Software Engineer to drive the technical vision for this platform-hands-on, comfortable with ambiguity, and effective at setting direction across teams. You will shape architectural decisions, mentor senior engineers, and raise the technical bar. We operate as a small, full stack, high autonomy team that values clear ownership, fast shipping cadence, and strong engineering velocity.