Senior Software Engineer - M365 Substrate Directory Platform

You’ll join the Substrate Directory Platform team, where we are modernizing how tenant-wide administrative data is stored, served, and operated at global scale. Working in the heart of M365, you’ll replace legacy directory paths with a durable, consistent, and resilient platform—one that becomes the long‑term source of truth for administrative operations across the cloud. As a Senior Software Engineer on the Substrate Directory Platform team, you will design, build, and operate distributed services, data models, and APIs that power tenant-wide administrative scenarios across Microsoft 365. You’ll take ownership of key system components, drive design and execution across complex problem spaces, and help evolve both the architecture and the operational maturity of the platform. This opportunity will allow you to accelerate your growth shipping cloud‑scale services, develop deep expertise in distributed systems and storage, and apply emerging AI techniques responsibly to real engineering challenges such as anomaly detection, incident summarization, and developer workflow automation. Hybrid work is supported per team and site guidelines. Microsoft’s mission is to empower every person and every organization on the planet to achieve more. As employees we come together with a growth mindset, innovate to empower others, and collaborate to realize our shared goals. Each day we build on our values of respect, integrity, and accountability to create a culture of inclusion where everyone can thrive at work and beyond.

Collaborate with appropriate stakeholders to define user requirements and translate ambiguous problem spaces into clear, actionable technical solutions. Drive the identification of dependencies and lead the development of design documents for product areas, services, or platforms with minimal oversight. Create, implement, optimize, debug, refactor, and reuse code to improve system performance, maintainability, reliability, and overall return on investment (ROI). Leverage deep understanding of product features to partner with program managers and other stakeholders in driving project plans, release strategies, and well-scoped work items. Act as a Designated Responsible Individual (DRI) for critical components; guide other engineers by establishing and following operational playbooks, participating in on‑call rotations, and leading mitigation and recovery for both simple and complex service issues. Proactively seek new knowledge and adopt modern patterns, tools, and AI‑assisted techniques that improve availability, durability, efficiency, observability, and operational consistency at scale.

Required Qualifications: Bachelor's Degree in Computer Science or related technical field AND 4+ years technical engineering experience with coding in languages including, but not limited to, C, C++, C#, Rust, Java, JavaScript, or Python OR equivalent experience. Other Requirements: Ability to meet Microsoft, customer and/or government security screening requirements are required for this role. These requirements include but are not limited to the following specialized security screenings: Microsoft Cloud Background Check: This position will be required to pass the Microsoft Cloud background check upon hire/transfer and every two years thereafter.

Master's Degree in Computer Science or related technical field AND 6+ years technical engineering experience with coding in languages including, but not limited to, C, C++, C#, Rust, Java, JavaScript, or Python OR Bachelor's Degree in Computer Science or related technical field AND 8+ years technical engineering experience with coding in languages including, but not limited to, C, C++, C#, Rust, Java, JavaScript, or Python OR equivalent experience.  Experience designing and operating distributed systems with clear guarantees around consistency, durability, availability, and well‑defined SLOs. Hands‑on