**Overview**

Microsoft Substrate is the foundational cloud platform that powers many of Microsoft’s most critical services including Exchange Online and M365 Copilot, providing shared infrastructure, identity, messaging, storage, and service-to-service capabilities used across Microsoft 365 and related cloud offerings. Substrate services operate at global scale and are designed to deliver high availability, reliability, and security for some of the world’s most demanding workloads.

As a **Principal Site Reliability Engineer** , you will set technical and operational direction for reliability across Substrate workloads. You operate at broad scope, influencing architecture, reliability strategy, and engineering practices across teams and organizations.

You are expected to lead complex, multi-year initiatives; shape how reliability is designed into systems; and act as a role model for technical excellence, leadership, and Microsoft values—particularly for servi...