Principal Software Engineer - Security

Overview

We are seeking a hands-on Principal Software Engineer (Security) with deep expertise in artificial intelligence security to take the lead in securing cutting-edge initiatives in Microsoft Edge. This Redmond-based role focuses on understanding existing and emerging threats, as well as cutting edge defenses, all within the context of a modern web browser. The ideal candidate has a solid background in AI (understanding how large language models work, prompt engineering, grounding techniques, when fine-tuning models is needed). While browser security domain knowledge is desirable, experience and expertise of AI integrations is paramount. This engineer will research new AI-driven vulnerabilities and implement practical mitigations to keep our users safe. The role is highly collaborative and requires excellent communication skills to work with multiple internal groups and external industry partners on securing AI features for modern AI browsers.

This role is about bringing top-tier AI security expertise into a browser security context. We need someone who can think like an attacker to anticipate how AI features could be abused, and act like an engineer to implement safeguards that make our browser and users safer. In doing so, you will elevate the security posture of Edge's AI capabilities and help shape industry-leading practices for securing AI in end-user applications.

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

• Partners with appropriate stakeholders to determine user requirements for one or more complex safety scenarios, including demonstration of security attacks, both practical contemporary attacks or future attacks.
• Provides technical leadership for the identification of dependencies and the development of design documents for Microsoft Edge and underlying AI platforms.
• Leads by example and mentors others to produce extensible and maintainable code used across the company.
• Leverages deep subject-matter expertise of cross-product features with appropriate stakeholders to lead multiple product's project plans, release plans, and work items.
• Holds accountability as a Designated Responsible Individual (DRI), mentoring engineers across products/solutions, monitoring system/product/service for novel security vulnerabilities.
• Proactively seeks new knowledge and adapts to new trends, technical solutions, and patterns that will improve the security baseline, efficiency, observability, and performance of products while also driving consistency in monitoring and operations at scale and shares knowledge with other engineers.

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, 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++, C#, Java, JavaScript, or Python
  • OR equivalent experience.
• 3+ years of experience in AI/ML security
  
  • OR equivalent recent security expertise.
• Demonstrated ability to apply AI knowledge in practice including prompt engineering
  
  • Or grounding
  • Or model fine tuning
• Demonstrated ability to both break systems and discover novel security flaws as well as building safeguards to mitigate them.
• Experience with Modern browsers, especially chromium-based browsers.
• Experience representing a team in multi-stakeholder environments.

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:
;br>
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.