(USA) Principal, Data Scientist

Role summary:

The Principal Data Scientist will lead the design, development, and deployment of AI-powered Search and Personalization systems serving hundreds of millions of customers across Walmart's global eCommerce platforms. This role demands deep expertise in information retrieval, ranking, recommendation systems, and Generative AI applied at production scale. You will define technical strategy, shape ML architecture, and partner with Product and Engineering to turn ambiguous discovery problems into measurable customer and business outcomes, while mentoring a team of senior scientists raising the bar across the discipline.

About the team:

Walmart's Search & Personalization team shapes how hundreds of millions of customers discover products every day. We sit at the intersection of AI research and global-scale systems, owning query understanding, retrieval, ranking, recommendations, and real-time personalization end to end. We work closely with Ads and Sparky, Walmart's AI shopping assistant, building the science that powers discovery across the full customer journey.

What you''ll do:

• Own end-to-end design and delivery of ML systems for Search ranking, query understanding, retrieval, recommendations, and real-time personalization.
• Build and productionize deep learning and Transformer-based models for relevance, intent classification, and semantic matching.
• Apply Generative AI and LLMs, including RAG and fine-tuning, to improve query understanding and product discovery.
• Design large-scale feature engineering and training pipelines handling petabyte-scale catalog and behavioral signals.
• Define experimentation strategies, offline evaluation frameworks, and online/offline metric alignment for Search and P13n systems.
• Drive technical architecture decisions and influence the long-term AI roadmap.
• Mentor senior scientists and establish team standards for model development and production deployment.

What you''ll bring:

• Proven track record in Search, Information Retrieval, Ranking, Recommendations, or Personalization at production scale.
• Hands-on experience with PyTorch and Transformer architectures for relevance modeling, semantic search, 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 ML pipelines.
• Solid command of experimentation: causal inference, A/B testing, interleaving, and offline/online metric alignment.
• Experience operationalizing ML systems at scale, including model serving, drift monitoring, and continuous training.
• Excellent communication skills and ability to lead multi-quarter technical initiatives across cross-functional teams.

At Walmart, we offer competitive pay as well as performance-based bonus awards and other great benefits for a happier mind, body, and wallet. Health benefits include medical, vision and dental coverage. Financial benefits include 401(k), stock purchase and company-paid life insurance. Paid time off benefits include PTO (including sick leave), parental leave, family care leave, bereavement, jury duty, and voting. Other benefits include short-term and long-term disability, company discounts, Military Leave Pay, adoption and surrogacy expense reimbursement, and more. You will also receive PTO and/or PPTO that can be used for vacation, sick leave, holidays, or other purposes. The amount you receive depends on your job classification and length of employment. It will meet or exceed the requirements of paid sick leave laws, where applicable. For information about PTO, see https://one.walmart.com/notices. Live Better U is a Walmart-paid education benefit program for full-time and part-time associates in Walmart and Sam''s Club facilities. Programs range from high school completion to bachelor''s degrees, including English Language Learning and short-form certificates. Tuition, books, and fees are completely paid for by Walmart.

Eligibility requirements apply to some benefits and may depend on your job classification and length of employment. Benefits are subject to change and may be subject to a specific plan or program terms.

For information about benefits and eligibility, see One.Walmart.

The annual salary range for this position is $143,000.00 - $286,000.00 Additional compensation includes annual or quarterly performance bonuses. Additional compensation for certain positions may also include :

• Stock