New 
Principal Software Engineer - M365 Copilot App
 Microsoft | |
 United States, California, Mountain View | |
 Oct 07, 2025 | |
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OverviewAI is transforming productivity in profound ways. As the new home of Office productivity, the M365 Copilot App is at the forefront of this transformation. It is one of the fastest growing products at Microsoft, and the primary means through which most M365 users experience the power of Copilot - be it Chat, Search, or Agents. M3CA is a multi-platform, cloud service backed product, and our team is responsible for all aspects of engineering for this ecosystem of endpoints and services. As a Principal Software Engineer on the team, you will be responsible for designing, building and running the Copilot app and backend service. You will lead architectural decisions and contribute hands-on code to advance the state of the art and build a best-in-class service, balancing innovation with platform stability. You will work closely with other engineers to take ideas through design, implementation, validation, and release. You will write secure, reliable, scalable, and high-performance code as well as automation to test it and telemetry to measure its behavior in production. You will work in a fast paced, highly collaborative environment to design, prototype, implement, and ship features. You will partner across multiple product and platform teams in Microsoft and define reusable architectural patterns and best practices that enable consistent, intelligent, and high-performing user experiences at scale. You will mentor engineers and promote a culture of high technical standards through best practices in architecture, performance profiling, and cross-platform design systems. You will provide engineering leadership to others on the team as they take on the engineering and technical responsibilities involved in building and delivering a global scale service that powers cross-platform AI experiences.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.
ResponsibilitiesPartners with appropriate stakeholders to determine user requirements for a set of scenarios.Leads identification of dependencies and the development of design documents for the product and service.Leads by example and mentors others to produce extensible and maintainable code used across products.Leverages subject-matter expertise of cross-product features with appropriate stakeholders (e.g., project managers) to drive multiple group's project plans, release plans, and work items.Holds accountability as a Designated Responsible Individual (DRI), mentoring engineers across the team, working on-call to monitor the product and service for degradation, downtime, or interruptions.Proactively seeks new knowledge and adapts to new trends, technical solutions, and patterns that will improve the availability, reliability, efficiency, observability, and performance of the product while also driving consistency in monitoring and operations at scale and shares knowledge with other engineers.Embody our culture and values. | |