Microsoft Defender protects individuals and enterprises from advanced cyber threats across Windows, macOS, Linux, Android, and iOS. We are expanding our tools and capabilities across product lines and seeking a Senior Software Engineer with deep expertise in C#, ASP.NET Core, HTML/CSS, and modern JavaScript to deliver secure, scalable, and intuitive experiences at global scale.

By streamlining infrastructure and developer tools, the Infrastructure and Developer Platform (IDP) team empowers engineers to build and scale services more efficiently and reliably. The Infrastructure and Developer Platform (IDP) team is a cornerstone of Microsoft’s security strategy, delivering the essential infrastructure that powers the Defender product suite. By offering robust tools and frameworks, IDP enables engineering teams to innovate rapidly while ensuring secure, reliable, and cost-effective service deployment. Leveraging cutting-edge technologies and best practices, the platform supports seamless operations and global protection for millions of users, reinforcing Microsoft’s leadership in cybersecurity.

You will own complex features end-to-end, influence architecture decisions, and mentor engineers while collaborating across disciplines to ship high-quality solutions that protect millions of devices worldwide.

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.

• Lead design and implementation of full-stack features spanning ASP.NET Core APIs, Razor/Blazor, and standards-based HTML/CSS/JavaScript.
• Define and evolve UI architecture and design patterns for enterprise-scale security solutions.
• Drive engineering excellence: testing strategies, CI/CD pipelines, code reviews, and documentation.
• Partner with PMs, designers, and platform teams to translate customer scenarios into technical plans.
• Champion accessibility (a11y), localization, and performance best practices across UI components.
• Mentor engineers on coding standards, design principles, and secure development practices.
• Stay current with emerging technologies and advocate for pragmatic innovation.

Required/minimum qualifications

Software Engineering IC4 - The typical base pay range for this role across the U.S. is USD $119,800 - $234,700 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 $158,400 - $258,000 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.