Senior Software Engineer - Backend

Senior Software Engineer - Backend

Welcome to CASQ – the team behind some of the most exciting AI experiences in Microsoft 365.

We build:

• M365 Copilot Chat – Microsoft’s flagship generative AI product.
• Copilot Search – a comprehensive enterprise search solution for M365.

We’re on a mission to reach 100M+ monthly active users by year-end and compete (and collaborate) with the best in the business, including our friends at OpenAI.

Role Overview

We are looking for a Senior Software Engineer to help build and evolve Copilot Search and BizChat experiences across Microsoft 365 (Teams, Outlook, Office, and Microsoft Search). This role sits at the intersection of large scale distributed systems, search & retrieval, and AI powered experiences, with a solid emphasis on quality, grounding, and customer trust.

As a Senior Software Engineer, you are expected to own complex problem areas end to end, drive execution across a feature or subsystem, and raise the engineering bar for quality, reliability, and operational excellence—while collaborating closely with PM, Applied Science, and partner teams.

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.

• Own and deliver complex features or subsystems within Copilot Search and BizChat, from design through production and iteration.
• Design, implement, and operate high scale backend services that power search, retrieval, grounding, and answer generation.
• Drive engineering quality across correctness, performance, reliability, security, and compliance.
• Partner closely with PM and Applied Science to translate customer and scenario needs into robust technical solutions.
• Lead execution across ambiguous problem spaces, decomposing work into milestones and driving delivery predictably.
• Diagnose and resolve live site issues, production regressions, and quality gaps using telemetry and data.
• Mentor and unblock other engineers, review designs and code, and model solid engineering practices.
• Collaborate across organizations (Teams, Outlook, M365, platform teams) to deliver integrated, end-to-end experiences.

Required Qualifications:

• Bachelor's Degree in Computer Science or related technical field AND 4+ years technical engineering experience with coding in languages including, but not limited to, C, C++, C#, Java, JavaScript, or Python.
  • OR equivalent experience.

Preferred Qualifications:

• Bachelor’s degree in Computer Science, Engineering, or equivalent practical experience.
• 6+ years of professional software engineering experience building and shipping production systems.
• Solid experience with distributed systems, backend services, or large-scale platforms.
• Proficiency in one or more of C++, C#, Java, or similar system level languages.
• Proven ability to design, implement, test, and operate production services.
• Experience working with data, telemetry, and live site diagnostics to drive quality.
• Experience in search, retrieval, ranking, recommendation systems, or AI powered applications.
• Familiarity with cloud platforms (Azure), service reliability, and operational best practices.
• Experience working in cross org, multiteam environments.
• Prior exposure to Copilot style scenarios, grounding, citations, or answer quality problems.
• Demonstrated mentoring or technical leadership within a team.

#CAPIDC

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.

Experience Level