About this role

Overview The Core OS (Operating Systems) Team is responsible for the foundational technologies that underpin Windows and Windows Server, providing the trusted platform on which customers run their most critical workloads. Our team combines deep systems engineering with modern Artificial Intelligence (AI) innovation to bring the next generation of intelligent capabilities to enterprise environments.We are hiring a Software Engineer II in Core OS to help build secure and reliable platform capabilities for Windows Server across on-premises, hybrid, and cloud-connected deployments. This is a hands-on engineering role where you will contribute to the implementation, testing, validation, and support of platform security features while collaborating with experienced engineers across the Windows Server ecosystem.You will help bring secure-by-design and secure-by-default ideas into production software by developing platform capabilities, automated validation solutions, telemetry, and diagnostics. You will work with engineers to translate security requirements, customer needs, and evolving threat landscapes into high-quality software that improves the security, reliability, and trustworthiness of Windows Server.At Microsoft, our mission—to empower every person and every organization on the planet to achieve more—guides how we partner with customers to deliver trusted, impactful solutions. With a growth mindset culture, we innovate responsibly and measure success by shared progress—people, teams, and customers. Join us to do meaningful work that changes the world and helps shape what’s next for everyone. Responsibilities <ul><li>Develop, test, debug, and maintain secure platform components and features for Windows Server using modern software engineering practices and AI-assisted development tools.</li><li>Design and implement automated validation, test, and fuzzing solutions that help improve software quality, reliability, security, and compatibility while preventing regressions.</li><li>Build telemetry, logging, diagnostics, and observability capabilities that provide insights into product health, reliability, performance, and security.</li><li>Participate in threat modeling, security reviews, and vulnerability mitigation efforts by implementing fixes, validating security invariants, and developing targeted test coverage.</li><li>Investigate product issues using debugging tools, logs, telemetry, and monitoring systems to identify root causes and contribute to corrective actions and long-term improvements.</li><li>Support security incident response activities by partnering with engineering, product, support, AI, and security teams to assess impact, diagnose issues, deliver fixes, and improve platform resilience.</li><li>Apply secure-by-design and secure-by-default principles, including secure coding practices, cryptographic standards, key management, auditability, and platform hardening techniques.</li><li>Participate in code reviews and design discussions, providing constructive feedback that improves code quality, reliability, maintainability, testability, and security.</li><li>Use AI-native engineering practices throughout the software development lifecycle, including code generation, testing, debugging, analysis, and documentation while maintaining accountability for the quality and correctness of all changes.</li><li>Collaborate with partner teams to deliver secure, scalable, and reliable solutions that meet Microsoft's security, privacy, compliance, accessibility, and operational standards.</li></ul> Qualifications Required Qualifications<ul><li>Bachelor's Degree in Computer Science or related technical field AND 2+ years technical engineering experience with coding in languages including, but not limited to, C, C++, C#, Java, JavaScript, or Python<ul style="list-style-type: circle;"><li>OR equivalent experience.</li></ul></li></ul>Preferred Qualifications<ul><li>3+ years of professional software engineering experience developing, testing, debugging, and maintaining software using one or more languages such as C, C++, C#, Python, Rust, PowerShell, or Kusto.</li><li>Experience designing automated tests, validation frameworks, telemetry, diagnostics, or developer productivity tools.</li><li>Experience or demonstrated interest in operating systems, virtualization technologies, systems programming, platform engineering, and software security.</li><li>Familiarity with AI-assisted software development tools and modern software engineering practices.</li><li>Familiarity with platform security technologies such as Secure Boot, Trusted Platform Module (TPM), virtualization-based security (VBS), code integrity, Credential Guard, WDAC/App Control, BitLocker, and Secured-core.</li><li>Understanding of common security concepts, secure coding practices, threat modeling fundamentals, and modern attack techniques such as credential theft, privilege escalation, persistence, and lateral movement.</li><li>Familiarity with cryptography fundamentals, security telemetry, observability, monitoring, and incident investigation.</li><li>Solid problem-solving, debugging, collaboration, and communication skills with a passion for learning and building secure, reliable systems.</li></ul>#W+DJOBS Software Engineering IC3 - The typical base pay range for this role across the U.S. is USD $102,100 - $202,200 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 $133,800 - $219,200 per year. Certain roles may be eligible for benefits and other compensation. Find additional benefits and pay information here: <a href="https://careers.microsoft.com/us/en/us-corporate-pay">https://careers.microsoft.com/us/en/us-corporate-pay</a> This position will be open for a minimum of 5 days, with applications accepted on an ongoing basis until the position is filled. <hr> 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 <a href="https://careers.microsoft.com/v2/global/en/accessibility.html">requesting accommodations.</a>