Microsoft Principal Software Engineer, Developer AI

New job, posted less than a week ago!

Job Details

Posted date: Jan 20, 2026

Category: Software Engineering

Location: Multiple Locations, Multiple Locations

Employment type: Full-Time

Work location type: 0 days / week in-office – remote

Role: Individual Contributor


Description

Overview

Within GitHub and Microsoft CoreAI, the Copilot CLI team builds GitHub’s coding agent in the terminal, and the core agent loop that powers agentic experiences across GitHub and Microsoft. Our work spans the full software development lifecycle, with a focus on turning modern AI systems into reliable, production-grade developer tools.

We are looking for a Principal Software Engineer / AI Engineer to help build a world-class coding agent CLI. This role is for engineers who care deeply about product quality, end-to-end ownership, and the details that separate promising tools from ones developers trust and adopt daily.

Our work sits at the intersection of agentic AI systems and high-performance developer tooling. We are particularly interested in candidates with strength in one or more of the following areas:

Building, evaluating, and iterating on agentic systems, including tool design, agent loops, benchmarking, and quality optimization

Building delightful, high-performance terminal experiences, including terminal UIs, low-level primitives, and systems that feel fast, predictable, and polished

Engineers on this team operate with high autonomy and a strong product mindset. You will own large surface areas end-to-end, partner closely with product and design, and push to continuously raise the quality bar for both the CLI and the underlying agent platform used across GitHub and Microsoft.

Microsoft’s mission is to empower every person and every organization on the planet to achieve more. As part of GitHub and CoreAI, we build developer tools that materially improve how software is written, reviewed, and shipped, while maintaining a culture of ownership, rigor, and technical excellence.

Responsibilities

Take ownership of critical product and platform areas of the Copilot CLI and shared agent runtime

Set a high technical and quality bar for agentic systems and developer-facing tooling

Design and ship performant, reliable terminal experiences that developers depend on for daily work

Use data, benchmarks, and direct user feedback to guide iteration and investment

Collaborate across org boundaries to enable other teams to build agentic products on top of a shared foundation

Influence architecture, technical direction, and engineering standards beyond your immediate team 

Qualifications

Main Requirements:

Hands-on experience building and operating generative AI or agentic systems in production, with direct ownership over quality, reliability, and iteration

5+ years of experience building and shipping customer-facing developer products, with depth across platform/foundation systems and user-facing experiences

Strong product mindset with a track record of owning ambiguous problem spaces and driving them to high-quality outcomes

Solid engineering fundamentals, including systems design, performance, and debugging in complex production environments

Experience designing, running, and optimizing evaluations for agentic systems, including tools, prompts, and agent loops

Experience building terminal user interfaces (TUIs) or working with low-level terminal primitives is a strong plus

Experience contributing to or leading open-source projects at scale is a plus

Additional 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.

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.



Email/text job link for Principal Software Engineer, Developer AI at Microsoft

Provide your email or phone number to recieve a short message with the job link and details.

Check out other jobs at Microsoft.