Principal Software Engineer

The Microsoft AI Web Data team is looking for a Principal Software Engineer to help us build the next generation platform for Bing and Microsoft AI. In Web Data, we are on a mission to build the most vast, safe, and accurate model of the Web to power search and AI. We are pushing frontiers of scalability and index quality by creating models and systems for discovering, storing, processing Web content, protecting our users & platform from Spam, Scams, and malware by keeping a step ahead of bad actors, and operating AI solutions. Our core set of engineering challenges includes:

• Discovering diverse content on the Web quickly and efficiently by understanding the structure and dynamics of the Web and optimizing crawl scheduling

• Building Big Data pipelines, creating ML and AI models for index selection, and determining document quality

• Building complex, Big Data pipelines, creating and deploying ML & AI models at Web scale for improving Safety by recognizing various forms of SEO Spam, Scams, Malicious webpages with exceptional Precision and Recall despite the rarity, and constant adversarial battle against bad actors.

• Designing and implementing models and pipelines for near-real time (NRT) indexing and content freshness

• Designing and implementing methods for leveraging AI in platform and backend solutions

This is a great opportunity for someone who loves to tackle deep technical challenges and strives for industry-wide impact. Someone who has the skill, will, and perseverence to steer a highly complex system, with many interdependencies, towards a better design. At this role, you would be advancing the platform and pipelines that powers the MAI Web Data's Safety systems, in a fundamentally new, modern direction. You'd be instantiating new technology into production to address Web Data product needs of the future. You will work on the design, development, execution, and implementation of technology at massive scale. You will work with Applied Scientists to develop, evaluate, operate, and/or deploy algorithms and solutions to improve or contribute to the creation of features and models with the highest system performance, quality, data management, and accuracy.

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

• You will partner with stakeholders within Safety, Web Data, and partner teams, to determine requirements, lead the identification of dependencies and the development of design documents, and drive project plans, release plans, and work items.

• You will lead by example, and mentor other engineers to produce extensible, scalable, high performance, resilient, and maintainable design and code.

• You will inspire accountability as a Designated Responsible Individual (DRI), mentoring engineers across teams, monitoring system/product/service for degradation, downtime, or interruptions, and proactively improving them.

• You will promote innovation and engineering excellence by seeking and sharing new knowledge and adapting to new trends, technical solutions, and patterns that will improve the availability, reliability, efficiency, observability, and performance of products while also driving consistency in monitoring and operations at scale, and sharing knowledge with other engineers and improving developer agility.

• 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.

Additional or Preferred Qualifications:

• Bachelor's Degree in Computer Science or related technical field AND 10+ years technical engineering experience with coding in languages including, but not limited to, C, C++, C#, Java, JavaScript, Python

• 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 equivalent experience.

• Experience with processing Terabyte to Petabyte scale data with efficient algorithms for feature engineering, and experience with optimizing for high inference ROI and deploying AI/ML models including, but not limited to, Decision Tree and Forest models, encoder only and generative LLM/SLM models, multi-modal models, on NVIDIA, AMD, TPU or equivalent accelerators.

• 3+ years of hands-on experience working with big data technologies (e.g., Hadoop, Spark, Kafka) or building highly scalable backend systems (e.g., distributed systems, microservices architecture, cloud-native services)

• Familiarity with Search stack and Grounding stack for AI Assistants, black-hat SEO and malicious techniques targeting traditional & generative search, and AI Assistants.

Microsoft is a global technology company headquartered in Redmond, Washington. Our mission is to empower every person and every organization on the planet to achieve more. We develop, license, and support a wide range of software products, services, and devices that help individuals and businesses realize their full potential.

Our flagship products include the Microsoft 365 productivity cloud, Windows operating system, Azure cloud platform, and Dynamics 365 business applications. We are also a leader in areas such as artificial intelligence, cybersecurity, developer tools, and gaming through Xbox and Game Pass.

With operations in more than 190 countries and over 220,000 employees worldwide, Microsoft is committed to responsible innovation, inclusive economic growth, and sustainability. We work closely with governments, industries, and communities to ensure that technology serves the public good and helps address some of the world’s most pressing challenges.

As we celebrate our 50th anniversary in 2025, we continue to look forward—investing in AI, cloud, and quantum computing to shape the future of work, education, and society at large scale.