We are seeking a Principal Software Engineer to join the Store Database Team within Microsoft's Substrate Storage Fabric. The team builds and operates core data infrastructure for Microsoft 365 experiences, such as Outlook and Teams, and AI-powered Copilot innovations. The ideal candidate will have deep experience and expertise in building ultra-high-scale storage and data access solutions. You will lead architecture, design, and delivery of large-scale storage platform capabilities, drive technical strategy, and partner with engineers and product managers to define technical direction. Responsibilities: Lead architecture, design, and delivery of large-scale storage platform capabilities Drive technical strategy and execution across complex initiatives Partner with engineers, product managers, and dependent service teams to define technical direction Lead design of AI-native systems and distributed storage architectures Establish technical standards and guardrails for AI-enabled solutions Use telemetry, experimentation, and data-driven analysis to identify bottlenecks and improve service health Lead live-site excellence and drive root-cause analysis and resiliency improvements Mentor engineers and technical leaders across the organization Qualifications: Bachelor's Degree in Computer Science or related technical field and 6+ years of technical engineering experience Ability to meet Microsoft, customer, and/or government security screening requirements Preferred Qualifications: Master's Degree in Computer Science or related technical field and 8+ years of technical engineering experience Deep expertise in distributed storage systems, databases, cloud infrastructure, and service architecture Experience designing and operating AI-native services and applying AI-assisted engineering practices