Senior Full Stack Engineer

Requisition Number: 2355284
Optum is a global organization that delivers care, aided by technology to help millions of people live healthier lives. The work you do with our team will directly improve health outcomes by connecting people with the care, pharmacy benefits, data and resources they need to feel their best. Here, you will find a culture guided by inclusion, talented peers, comprehensive benefits and career development opportunities. Come make an impact on the communities we serve as you help us advance health optimization on a global scale. Join us to start Caring. Connecting. Growing together.
Primary Responsibilities:

• QE & Automation Foundations
  • Solid QE fundamentals: test strategy, test planning, defect lifecycle
    • Functional, integration, regression testing
    • API testing (REST, JSON, Postman)
    • Test automation using Python / JavaScript
    • CI/CD awareness (Git, pipelines, build verification)
    • Log analysis & debugging (CloudWatch / centralized logging)
• Conversational AI Testing
  • Intent, utterance, slot/entity testing (Amazon Lex or similar)
    • Multi turn conversation validation
    • Context & session management testing
    • Interruptions, re phrasing, intent switching
    • Fallback, disambiguation, error handling scenarios
    • Voice vs Chat behavior differences (ASR errors, latency, barge in)
    • Bot → Agent handoff validation
• Agentic AI Testing
  • Clear understanding of agentic behavior (plan → reason → act → observe)
    • Testing non deterministic responses
    • Multi step workflow validation
    • Tool / API invocation correctness by agents
    • Agent memory & state validation across turns
    • Boundary based validation (acceptable vs unacceptable outcomes)
    • Guardrail enforcement testing (what agent must NOT do)
• LLM & Prompt Quality Engineering
  • Prompt structure understanding (system vs dynamic prompts)
    • Prompt regression testing
    • Prompt versioning & rollback validation
    • Hallucination detection & containment
    • Response tone, empathy, policy compliance validation
    • Safety, toxicity, and unsafe response testing
• Production Readiness & Observability
  • AI production defect RCA
    • Monitoring AI KPIs:
      • Containment rate
    • Escalation rate
    • Conversation success/failure
    • Hallucination incidents
    • Latency, retries, throttling, timeout scenarios
    • Release readiness sign off for AI systems
• Security, Privacy & Compliance
  • PII / PHI masking validation
    • Data boundary validation (what is sent to LLM vs retained)
    • Prompt leakage risk testing
    • Secure handling of logs and conversation transcripts
    • Compliance aware test scenarios (healthcare grade rigor)
• Comply with the terms and conditions of the employment contract, company policies and procedures, and any and all directives (such as, but not limited to, transfer and/or re-assignment to different work locations, change in teams and/or work shifts, policies in regards to flexibility of work benefits and/or work environment, alternative work arrangements, and other decisions that may arise due to the changing business environment). The Company may adopt, vary or rescind these policies and directives in its absolute discretion and without any limitation (implied or otherwise) on its ability to do so

Required Qualifications:

• Fulltime Graduation degree
• Skills:
  • Advanced AI Evaluation
    • LLM as Judge concepts
      • Human in the loop evaluation
      • Golden dataset creation
      • Automated quality scoring frameworks
  • Advanced Automation & Scale
    • Conversation simulation frameworks
      • Synthetic utterance / conversation generation
      • Data driven AI test automation
      • AI assisted test case generation
  • Platform & Architecture Awareness
    • Experience with Agent Orchestrators
      • Multi agent coordination testing
      • RAG pipeline understanding
      • Integration testing across IVR, CRM, backend systems
  • Quality Leadership & Collaboration
    • Risk based testing mindset
      • Ability to challenge product assumptions
      • Solid collaboration with Product, AI Engineers, Ops
      • Executive ready quality metrics & reporting
      • Comfort with ambiguity and evolving AI behavior

Preferred Qualifications:

• Masters in AI / ML, Engineering, Mathematics, Statistics, or a related discipline
• Experience working with cross-functional and distributed teams in a global and diverse environment
• Experience in mentoring, coaching, and developing AI/ML talent
• Experience in establishing and enforcing AI/ML best practices, standards, and ethics
• Experience in Realizing Value from AI/ML products as well as production ready product.
• Proven history of delivering high-impact AI/ML solutions for real-world problems and use cases
• Proven background in healthcare (AI)
• Proven portfolio of AI/ML publications, patents, or awards

At UnitedHealth Group, our mission is to help people live healthier lives and make the health system work better for everyone. We believe everyone-of every race, gender, sexuality, age, location and income-deserves the opportunity to live their healthiest life. Today, however, there are still far too many barriers to good health which are disproportionately experienced by people of color, historically marginalized groups and those with lower incomes. We are committed to mitigating our impact on the environment and enabling and delivering equitable care that addresses health disparities and improves health outcomes - an enterprise priority reflected in our mission.
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