Principal Software Engineer--M365 Networking Team
Confirmed on the employer's own hiring board on Sep 30, 2026. First seen by Alion on Sep 24, 2026. Microsoft scores B on the Alion truth index.
We are looking for a highly motivated Principal Software Engineer who is passionate about building intelligent, scalable, and resilient systems at the heart of Microsoft 365’s infrastructure. You will join the M365 Networking team, building routing, traffic-management, and load-balancing capabilities that help deliver reliable, efficient, and secure connectivity for Microsoft 365 workloads, including Copilot, Teams, and SharePoint Online.
About the Team
The M365 Networking team focuses on connecting requests to the right service endpoints across Microsoft 365’s global infrastructure. Our work spans routing, traffic management, and load balancing to improve service availability, minimize latency, and efficiently utilize capacity. We tackle distributed-systems challenges at massive scale, with a focus on technical excellence, innovation, and operational impact.
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
- Design and implement routing, traffic-management, and load-balancing capabilities to support scenarios across M365, including Copilot.
- Optimize traffic distribution based on service health and available capacity to improve performance, resilience, and resource utilization.
- Build distributed, highly available, and resilient systems.
- Work with services spanning thousands of servers, processing tens of billions of transactions, and serving hundreds of millions of users.
- Drive technical excellence through code reviews, architecture design.
Qualifications
Required Qualifications:
- Bachelor'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#, 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 8+ years technical engineering experience with coding in languages including, but not limited to, C, C++, C#, Java, Rust, or Python
- OR Bachelor'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, Rust, or Python or equivalent experience.
- Solid understanding of computer science fundamentals, including data structures, algorithms, and object-oriented design.
- Experience developing, testing, and debugging backend services or distributed systems.
- Demonstrated problem-solving skills, with the ability to diagnose software issues and deliver reliable, maintainable solutions.
- Effective communication and collaboration skills, with the ability to work across teams to deliver features end to end.
- 3+ years of industry experience in service development, successfully shipping services through multiple releases.
- Solid understanding of distributed systems; experience with networking, traffic management, or load balancing is a plus.
- Familiarity with AI/ML-driven decision systems.
- A passion for quality and a record of delivering results while working on large-scale distributed systems.
- Experience developing large-scale online services with robust performance, resiliency, telemetry, and security.
- Effective communication and collaboration skills, including working across organizational boundaries in a dynamic, agile environment.
- A self-motivated, customer-focused approach and a passion for improving engineering practices and producing high-quality software.
- Experience with DNS architecture, resolution, and troubleshooting, particularly in large-scale cloud services; familiarity with DNS-based traffic management and load balancing is a plus.
This position will be open for a minimum of 5 days, with applications accepted on an ongoing basis until the position is filled.
Microsoft is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to age, ancestry, citizenship, color, family or medical care leave, gender identity or expression, genetic information, immigration status, marital status, medical condition, national origin, physical or mental disability, political affiliation, protected veteran or military status, race, ethnicity, religion, sex (including pregnancy), sexual orientation, or any other characteristic protected by applicable local laws, regulations and ordinances. If you need assistance with religious accommodations and/or a reasonable accommodation due to a disability during the application process, read more about requesting accommodations.