Senior AI/ML Engineer

This Senior AI/ML Engineer role at Optum (part of UnitedHealth Group) focuses on building and deploying machine learning and generative AI solutions for U.S. healthcare. You will work across the full ML lifecycle, including data preparation, model development, evaluation, deployment, and monitoring, with an emphasis on RAG, agentic workflows, and responsible AI. The role offers a hybrid work model from Dublin or Letterkenny, Ireland.

• Design, build, and deploy generative AI solutions including retrieval-augmented generation, prompt and context engineering, orchestration, and agentic workflows grounded in enterprise healthcare data
• Develop and productionize classical machine learning models, covering feature engineering, training, tuning, validation, and inference
• Build evaluation harnesses, test sets, and quality metrics to measure model and GenAI system performance including accuracy, groundedness, latency, and cost
• Implement MLOps practices such as experiment tracking, model registries, automated pipelines, CI/CD, and monitoring for drift, quality, and reliability in production
• Work with data engineering to shape datasets, semantic layers, and retrieval indexes that AI and ML workloads depend on
• Partner with product, business, architecture, security, and governance stakeholders to turn use cases into workable solutions and explain model capabilities and limitations
• Apply responsible AI practices including privacy, safety, bias assessment, human-in-the-loop review, and traceability for sensitive and regulated data