Principal Software Engineer - CTO OFFICE

Overview 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. The Applied AI Scientist will explore and advance frontier AI technologies to create differentiated security capabilities. The role focuses on developing and validating novel AI methods, experimenting with emerging techniques, and adapting state-of-the-art models and learning approaches to complex security problems. Responsibilities Explore frontier AI techniques, including reasoning models, autonomous agents, retrieval, fine-tuning, and Reinforcement Learning Environments (RLE). Design and execute experiments to evaluate AI capabilities, limitations, and effectiveness in security scenarios. Develop novel approaches to model adaptation, agent behavior, and AI-powered security solutions. Build evaluation frameworks to measure performance, reliability, and effectiveness. Translate emerging AI research into technically validated solutions and differentiated intellectual property. Collaborate with engineering and product teams to transition successful experiments toward productization. Qualifications Strong background in machine learning, deep learning, and modern generative AI technologies, including Large Language Models (LLMs). Hands-on experience developing, experimenting with, and evaluating advanced AI models and techniques, beyond basic API integration. Experience with frontier AI techniques such as agentic AI, reasoning models, reinforcement learning, fine-tuning, and retrieval-augmented generation (RAG). Preferred Qualifications Master's or Ph.D. in Computer Science, Artificial Intelligence, Machine Learning, or a related technical field, or equivalent practical experience. 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.