Principal Software Engineer

Overview

At Microsoft Edge, performance defines the user experience. We are looking for a Principal Software Engineer to help shape the future of browser performance across real‑world scenarios—navigating websites, interacting with content, scrolling pages, and responding instantly to user input. In this role, you will own performance outcomes for major browser subsystems and help ensure Edge feels fast, responsive, and reliable for millions of users every day.

You will lead the design and evolution of systems that make performance durable as the product grows. This includes setting architectural direction, modernizing legacy implementations, and establishing clear performance patterns so new features ship with performance built in—not added later. You will work hands‑on in the codebase, using real user signals, traces, and data to understand where time is spent and to drive deep improvements in navigation, input responsiveness, startup, and ongoing interaction quality.

Your impact will scale through systems and influence. You will advance performance tooling, automation, and AI‑assisted diagnostics to help teams detect, understand, and prevent performance issues before they reach customers. Partnering closely with feature teams, you will help make performance a first‑class design constraint across Edge. Success in this role is measured by sustained improvements in real user experiences—faster interactions, smoother input, fewer recurring regressions, and a higher performance bar across the organization.

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.

Starting January 26, 2026, Microsoft AI (MAI) employees who live within a 50- mile commute of a designated Microsoft office in the U.S. or 25-mile commute of a non-U.S., country-specific location are expected to work from the office at least four days per week. This expectation is subject to local law and may vary by jurisdiction.

Responsibilities

• Own performance outcomes for Microsoft Edge user scenarios including site navigation, scrolling, input responsiveness, and startup.
• Lead architectural evolution to ensure browser performance remains durable as Edge scales and evolves.
• Drive data‑informed performance improvements using real‑world telemetry, traces, and experiments.
• Modernize legacy implementations and establish clear performance‑focused coding patterns and quality bars.
• Partner with feature teams to make performance a first‑class design constraint from concept to ship.
• Scale impact through performance tooling, automation, and AI‑assisted diagnostics to prevent regressions.

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++, Rust, C#, Java, JavaScript, or Python OR equivalent experience.

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++, Rust, C#, Java, JavaScript, 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++, Rust, C#, Java, JavaScript, or Python OR equivalent experience.

3+ years experience designing and shipping performance-critical, large-scale software with measurable user impact (e.g., navigation, scrolling, input responsiveness, startup).

Proven ability to drive architectural changes and modernize complex/legacy codebases to improve performance, reliability, and maintainability.