Principal Software Engineer

Overview

Microsoft 365 Copilot is a groundbreaking productivity tool that leverages the power of large language models, user data, Microsoft Graph, and the web to drive unparalleled creativity and productivity. At the heart of this innovation is the Copilot Agent Platform, which designs and operates the agent runtime, integrations across M365 apps, and platform to build features that flow consistently to Flagship, 1P, and 3P agents. Our team is building a modular, event‑driven platform that raises agility, reliability, and composability for every Copilot experience. 

We are looking for a Principal Software Engineer to help us deliver the next generation of the Copilot Agent Platform. You will design, develop, and harden core platform capabilities, real‑time multimodal orchestration, long‑running task durability, and self‑serve partner tooling to unlock safe, rapid innovation across the ecosystem. 

As a Principal Software Engineer, you will be responsible for designing, developing, and delivering innovative platform services. You’ll code, debug, test, and troubleshoot production systems that other agents depend on; contribute to safe deployment practices and flighting; build robust telemetry and evals; and collaborate with partner teams to ship features once and light them up everywhere. 

In this role, you are expected to have a deep understanding of distributed systems and apply software engineering principles to create high‑quality, observable, and reliable services. You will work closely with other engineers and PMs to ensure our platform meets partner and user needs, adheres to M365 Core engineering standards, and is delivered with guardrails that protect reliability and customer trust. 

You will have the opportunity to grow your skills and take on new challenges—ranging from runtime/orchestration and real‑time multimodal to API/protocol design and developer experience while operating at the core of M365 where your work scales across Outlook, Teams, Word, Excel, PowerPoint, and more. Join us and help build the platform that powers the next generation of Copilot agents. 

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. 

Responsibilities

• Guides engineers within and across teams to produce extensible, maintainable, well‑tested, secure, and performant code that adheres to design specifications.
• Partners with appropriate stakeholders to determine user requirements for one or more complex scenarios.
• Provides technical leadership in identifying dependencies and developing design documents for a product, application, service, or platform.
• Leads by example and mentors others to produce high‑quality code used across the company, promoting engineering excellence and long‑term maintainability.
• Leverages deep subject‑matter expertise of cross‑product features to collaborate with stakeholders and lead multiple products’ project plans, release plans, and work items.
• Holds accountability as a Designated Responsible Individual (DRI), mentoring engineers across products/solutions and participating in on‑call rotations to monitor system/product/service health, including degradation, downtime, or interruptions.
• Proactively seeks new knowledge and adapts to emerging trends, technologies, and patterns to improve availability, reliability, efficiency, observability, and performance, while driving consistency in monitoring and operations at scale; shares learnings with other engineers.
• Embody our Culture and Values 

Qualifications

Required Qualifications:

• 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#, 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.
Preferred Qualifications:

• Master's Degree in Computer Science or related technical field AND 12+ years technical engineering experience with coding in languages including, but not limited to, C, C++, C#, Java, JavaScript, or Pyt