Senior, Data Scientist - Conversational AI

Position Summary...

The Cortex Team is Walmart’s core AI conversational platform, powering the vision of delivering the world’s best personal assistants to Walmart’s customers through natural voice commands, text messages, rich UI interactions, and multi-modal experiences.

We believe conversations are a natural and powerful user interface that enables richer customer experiences online and in-store. We are developing next-generation Natural Language Understanding (NLU) services that are easy for other teams to integrate and leverage, supporting various experiences from voice and text shopping assistants to customer care channels and multi-modal mobile apps.

We are seeking passionate and experienced NLP data scientists to enhance our capabilities, considering full conversational context, multi-modal interactions, and expanding use cases.

Joining us now offers the chance to significantly impact the design, architecture, and implementation of a critical, data-driven product used daily and loved by customers. You will also have opportunities to create demos, proofs of concept, white papers, and blogs.

Minimum Qualifications

• Experience with Python and solid knowledge of SQL.
• At least five years of hands-on experience with classical ML models, including test/train/evaluation metrics and key parameters affecting model performance.
• Understanding of statistical measures such as confidence intervals and error significance, along with development and evaluation datasets.
• Familiarity with NLP/NLU, deep ML models (Transformers, BERT, Llama, GPTs, Gemini), and safe fine-tuning of these models.
• Strong analytical skills and ability to communicate results clearly.
• Experience analyzing data, identifying patterns, and conducting error analysis.
• Ability to manage projects from scoping to launch.
• Continuous drive to improve and optimize models and products.
• Excellent communication skills.
• Bachelor’s degree or certification in relevant fields such as Machine Learning, CS, Engineering, Mathematics, or Statistics.

Preferred Qualifications

• Experience with production-grade agentic systems.
• Knowledge of LLMs serving optimizations and multi-LoRa.
• Ability to develop experimental and analytical plans, establish strong baselines, and determine cause-effect relationships.
• Attention to detail and strong organizational skills.
• Proven results in fast-paced, collaborative environments.
• Hands-on experience across data pipelines, model training, deployment, ML-ops, and related tools.
• PhD in relevant fields preferred.

Walmart offers competitive pay, performance bonuses, comprehensive health benefits, 401(k), stock options, paid time off, and other perks. For more details, visit One.Walmart .

Locations and Salary

Sunnyvale, CA: $117,000 - $234,000 annually
Bellevue, WA: $108,000 - $216,000 annually
Additional compensation includes bonuses and stock options.

Primary Location

680 West California Avenue, Sunnyvale, CA , United States