Principal Applied Scientist

The Copilot Agents & Search Quality team develops state-of-the-art machine learning, retrieval, ranking, and generative AI technologies that power Microsoft Copilot. We solve complex real-world challenges in relevance, personalization, and information discovery at global scale, helping millions of enterprise users find the right information, at the right time, and in the right context.

We are looking for a Principal Applied Scientist with deep expertise in applied AI and a proven track record of building and shipping machine learning solutions at scale. The ideal candidate will have extensive hands-on experience developing and optimizing modern AI systems, including Small Language Models (SLMs), post-training techniques, embedding models, encoder-decoder and cross-encoder architectures, and Gradient Boosted Tree (GBT) models trained on large-scale datasets.

This is a unique opportunity to help shape the next generation of Microsoft's search and retrieval stack, driving innovations that power Copilot experiences for millions of users worldwide.

You will join a fast-paced, highly collaborative environment and work closely with experts across Microsoft, including Microsoft Research, to advance the state of the art in AI-powered search, retrieval, ranking, and knowledge discovery. Our work spans cutting-edge embedding models, cross-encoders, SLMs, deep neural networks, and classical machine learning approaches, with a strong focus on delivering measurable impact in production.

Successful candidates will have a demonstrated history of leading complex technical initiatives, influencing technical strategy, and driving execution across teams while mentoring other scientists and engineers.

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.

Responsibilities

• Advance the science: Design and run experiments, define and validate metrics, and develop ML pipelines and models in areas like encoder-decoder models, cross-encoder models. You will also experiment with SLMs + model distillation to bring the power of Language models optimized for focused ranking tasks within low latency constraints. This is a strategic initiative and you are expected to drive this by working with different leaders across the org to drive clarity and alignment. You will be working with large scale data and derive insights out of it while championing Privacy and Compliance.