(USA) Staff, Data Scientist

Walmart • Sunnyvale, CA

1d • $143,000 - $286,000 • Onsite

About The Position

As a Staff Data Scientist at Walmart, you will leverage advanced analytical techniques and machine learning to transform complex data into actionable business insights. This role requires designing, implementing, and scaling high-throughput supervised fine-tuning (SFT) pipelines to train foundation models to follow user prompts, perform ranking tasks, and optimize training hyperparameters such as learning rate schedules and related configurations. You will collaborate across functions to identify and evaluate data sources, ensure data quality, and communicate findings through effective visualizations. Your contributions will drive innovation and operational excellence by applying rigorous statistical methods and scalable solutions that align with Walmart's strategic objectives and commitment to delivering customer value. About the Team Our team develops foundational models tailored for Walmart's e-commerce platform by leveraging large-scale user interactions to create rich representations of users, products, and search queries. These models power scalable search, advertising, recommendation, and personalization solutions. Team members apply expertise in data science, machine learning, and software engineering to optimize model performance, training, and deployment. With a strong focus on data quality, advanced analytics, and impactful visualization, the team delivers actionable insights that influence key business outcomes. Cross-functional collaboration drives innovation and enables continuous improvement in data-driven decision-making within a dynamic technology environment.

Requirements

• Proven expertise in data science, including predictive analytics, machine learning algorithms, statistical modeling, and hypothesis testing.
• Strong programming skills in Python and experience with data visualization tools such as Matplotlib, Plotly, Tableau, or Power BI.
• Hands-on experience designing, training, and deploying machine learning models, with a focus on transformer-based architectures and large language models.
• Experience optimizing large-scale training pipelines, including hyperparameter tuning and implementing high-throughput workflows using frameworks such as PyTorch.
• Experience applying reinforcement learning methods (e.g., RLHF) for preference optimization, model alignment, and safety-focused applications.
• Demonstrated ability to translate complex business requirements into analytical models and actionable business insights.
• Excellent verbal and written communication skills, with the ability to present technical findings effectively to both technical and non-technical stakeholders.

Nice To Haves

• Data science, machine learning, optimization models
• PhD in Machine Learning, Computer Science, Information Technology, Operations Research, Statistics, Applied Mathematics, Econometrics
• Successful completion of one or more assessments in Python, Spark, Scala, or R
• Using open source frameworks (for example, scikit learn, tensorflow, torch)
• Creating inclusive digital experiences, demonstrating knowledge in implementing Web Content Accessibility Guidelines (WCAG) 2.2 AA standards, assistive technologies, and integrating digital accessibility seamlessly.
• Knowledge of accessibility best practices and joining Walmart in its efforts to create accessible products and services following Walmart’s accessibility standards and guidelines for supporting an inclusive culture.

Responsibilities

• Identify and evaluate data sources aligned with business requirements and quality standards.
• Design, implement, and scale high-throughput SFT pipelines to train foundation models for instruction following, ranking, and related tasks.
• Manage high-quality dataset mixtures and optimize training hyperparameters, including learning rate schedules and other training configurations.
• Drive model alignment toward helpfulness, accuracy, and safety through preference optimization techniques and reinforcement learning approaches.
• Create clear, insightful visualizations to effectively communicate findings and recommendations to stakeholders.
• Translate complex business challenges into data-driven solutions and actionable insights.
• Collaborate with cross-functional teams to deploy, monitor, and improve machine learning models in production environments.
• Mentor junior team members on analytical methodologies, coding best practices, machine learning techniques, and data storytelling.

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 leave
• Short-term disability
• Long-term disability
• Company discounts
• Military Leave Pay
• Adoption and surrogacy expense reimbursement
• PPTO that can be used for vacation, sick leave, holidays, or other purposes
• Walmart-paid education benefit program (Live Better U) for full-time and part-time associates

What This Job Offers

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