New

Principal Software Engineer

Microsoft
$139,900.00 - $274,800.00 / yr
United States, Washington, Redmond
Jan 22, 2026
Overview Microsoft 365 Copilot Chat is the conversational core of Microsoft's enterprise AI productivity strategy. It is the front door toAIpoweredwork--enabling customers to summarize meetings, draft content, collaborate using natural language, and get work done across Microsoft 365. Client performance, reliability, and UX quality are foundational to customer trust and adoption of Copilot Chat at enterprise scale.Serversiderendering (SSR), hydration correctness, and resilient client behavior directlyimpactperceived responsiveness, reliability, and user confidence. We are seeking aPrincipal Software Engineerto define, build, and evolve theperformancecritical, SSRbacked Copilot Chat experience. This is a senior individual contributor role withplatformlevelownership, technical leadership, and deep influence across Microsoft 365 surfaces. Responsibilities Leadarchitectural improvementsto theM365Copilot Chat frontend platform to improve performance, reliability, and developer velocity at scale. Design, build, and evolvehighquality,performancesensitiveUX for Microsoft 365 Copilot Chat using modern frontend technologies. Ownserversiderendering (SSR) and client hydration correctnessacross key Copilot Chat user journeys to ensure fast perceived performance and resilient behavior. Translate UX and product specifications intopixelperfect,productionreadyimplementationswith high attention to performance and accessibility. Collaborate closely withProduct Managers, Designers, and partner engineering teamsto land features across Microsoft 365 surfaces. Qualifications Required Qualifications: Bachelor's Degree in Computer Science or related technical field AND 6+ years of technical engineering experience with coding in languages including, but not limited to, C++, C#,REACT, TypeScript, HTML, or CSS 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#,REACT, TypeScript, HTML, or CSS 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#, REACT, TypeScript, HTML, or CSS OR equivalent experience. 8+ yearsof professional software engineering experience, withfocusonfrontendor UX engineering. Hands on experience building and operatingserversiderendered(SSR) web applicationswith robust client hydration at production scale. Proficiency with understanding web performance fundamentals, including rendering, loading, caching, and perceived performance. Proficiency with debugging skills across client, network, and SSR execution paths in large, complex code bases. Experience collaborating across teams and navigating dependencies in large engineering organizations. Software Engineering IC5 - The typical base pay range for this role across the U.S. is USD $139,900 - $274,800 per year. There is a different range applicable to specific work locations, within the San Francisco Bay area and New York City metropolitan area, and the base pay range for this role in those locations is USD $188,000 - $304,200 per year. Certain roles may be eligible for benefits and other compensation. Find additional benefits and pay information here: https://careers.microsoft.com/us/en/us-corporate-pay 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.