(USA) Principal, Data Scientist

Walmart • Sunnyvale, CA

7d • Onsite

About The Position

The Principal Data Scientist will lead the development and deployment of advanced analytical models and machine learning solutions to address complex business challenges. This role requires deep expertise in statistical analysis, AI, and data strategy to translate business needs into scalable, data-driven solutions. The position involves mentoring team members, collaborating cross-functionally, and ensuring the quality and impact of data initiatives. The successful candidate will drive innovation through rigorous testing, model validation, and continuous improvement, supporting Walmart’s commitment to operational excellence and delivering measurable business value. Walmart's Search & Personalization team drives how millions of customers find and engage with products daily. Positioned at the intersection of AI research and large-scale systems, the team owns recommendations, real-time personalization, user modeling, ranking, and behavioral intelligence end to end. Collaborating closely with Ads and Sparky, Walmart's AI shopping assistant, the team develops advanced science that delivers tailored shopping experiences throughout the customer journey. This group leverages expertise in machine learning, deep learning, and AI to build innovative solutions that improve customer engagement, conversion, and business outcomes on a global scale.

Requirements

• Proven track record building Recommendation Systems, Personalization platforms, or user-facing ranking models at production scale.
• Hands-on experience with PyTorch and Transformer architectures for sequential modeling, user/item embeddings, or multi-task learning.
• Practical experience applying Generative AI to real products, including RAG, instruction fine-tuning, or RLHF.
• Strong engineering skills in Python and Scala, with experience building large-scale Spark-based behavioral signal pipelines.
• Solid command of experimentation: causal inference, A/B testing, interleaving, and offline/online metric alignment for personalization systems.
• Experience operationalizing ML systems at scale, including real-time model serving, drift monitoring, and continuous training.
• Excellent communication skills and ability to lead multi-quarter technical initiatives across cross-functional teams.
• Bachelors degree in Statistics, Economics, Analytics, Mathematics, Computer Science, Information Technology or related field and 5 years' experience in an analytics related field.
• Masters degree in Statistics, Economics, Analytics, Mathematics, Computer Science, Information Technology or related field and 3 years' experience in an analytics related field.
• 7 years' experience in an analytics or related field

Nice To Haves

• Data science, machine learning, optimization models
• PhD in Machine Learning, Computer Science, Information Technology, Operations Research, Statistics, Applied Mathematics, Econometrics
• Publications or active peer reviewer in related journals or conference
• Successful completion of one or more assessments in Python, Spark, Scala, or R
• Using open source frameworks (for example, scikit learn, tensorflow, torch)
• We value candidates with a background in creating inclusive digital experiences, demonstrating knowledge in implementing Web Content Accessibility Guidelines (WCAG) 2.2 AA standards, assistive technologies, and integrating digital accessibility seamlessly.
• The ideal candidate would have knowledge of accessibility best practices and join us as we continue to create accessible products and services following Walmart’s accessibility standards and guidelines for supporting an inclusive culture.

Responsibilities

• Own end-to-end design and delivery of personalization ML systems spanning recommendations, user modeling, real-time ranking, and personalized product discovery.
• Build and productionize deep learning models for CTR/CVR prediction, sequential recommendation, and user/item representation learning.
• Apply Generative AI and LLMs, including RAG and fine-tuning, to deliver personalized shopping experiences across the customer journey.
• Design large-scale behavioral feature pipelines handling petabyte-scale user interaction signals in Spark and Scala.
• Define experimentation strategies, offline evaluation frameworks, and online/offline metric alignment for P13n systems.
• Drive personalization architecture decisions and influence the long-term AI roadmap.
• Mentor senior scientists and establish team standards for model development and production deployment.

Benefits

• Competitive pay
• Performance-based bonus awards
• Medical coverage
• Vision coverage
• Dental coverage
• 401(k)
• Stock purchase
• Company-paid life insurance
• PTO (including sick leave)
• Parental leave
• Family care leave
• Bereavement
• Jury duty
• Voting
• Short-term disability
• Long-term disability
• Company discounts
• Military Leave Pay
• Adoption and surrogacy expense reimbursement
• PTO and/or PPTO that can be used for vacation, sick leave, holidays, or other purposes
• Live Better U (Walmart-paid education benefit program for full-time and part-time associates)

What This Job Offers

• Job Type: Full-time
• Career Level: Principal