Full Stack Engineer

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.

 

Software engineering is the application of engineering to the design, development, implementation, testing and maintenance of software in a systematic method. The roles in this function will cover all primary development activity across all technology functions that ensure we deliver code with high quality for our applications, products and services and to understand customer needs and to develop product roadmaps.

 

These roles include, but are not limited to analysis, design, coding, engineering, testing, debugging, standards, methods, tools analysis, documentation, research and development, maintenance, new development, operations and delivery. With every role in the company, each position has a requirement for building quality into every output. This also includes evaluating new tools, new techniques, strategies; Automation of common tasks; build of common utilities to drive organizational efficiency with a passion around technology and solutions and influence of thought and leadership on future capabilities and opportunities to apply technology in new and innovative ways.

 

Primary Responsibilities:

• Build and maintain Python async backend services with Pydantic validation exposing REST/JSON or WebSocket endpoints for conversational clients
• Implement LLM-enabled workflows and agent orchestration using LangGraph, LangChain, or similar frameworks supporting tool-calling/function-calling and multi-step patterns (planner/worker/solver, ReACT)
• Integrate cloud services (Azure or equivalent) for hosting, identity, secrets, persistence and monitoring, and implement session/conversation stores with optional vector/embedding-backed RAG
• Apply resiliency patterns (timeouts, retries/backoff, rate-limiting), consistent error handling, and correlation ID propagation for traceability
• Build React 18 + TypeScript components for chat, streaming/partial responses, and tool-invocation flows with baseline accessibility (ARIA) and Storybook-driven development
• Use monorepo/workspace tooling (yarn/pnpm, Vite, Storybook, ESLint, Prettier) and write automated tests (pytest/pytest-asyncio, Jest/RTL, Cypress) integrated into CI
• Instrument and debug distributed systems with structured logs and traces (OpenTelemetry) and help operationalize monitoring, alerting and LLM cost-awareness
• Collaborate in design discussions and code reviews, contribute to shared libraries and developer workflows, and implement secure secret handling and guardrails for tool execution
• Basic, structured, standard approach to work
• 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 regard 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

Qualifications - External

Required Qualifications:

• 4+ years building production full-stack applications with practical experience in Python and React/TypeScript
• Hands-on experience integrating LLMs (OpenAI or equivalents) and agent frameworks (LangGraph, LangChain or similar) for tool-calling and multi-step orchestration
• Proficient in async Python service development, API design, and Pydantic schema validation
• Familiarity with cloud platforms (Azure preferred) and enterprise patterns for identity, secrets, managed data stores and observability
• Solid testing skills across backend and frontend (pytest, pytest-asyncio, Jest, React Testing Library, Cypress) and CI integration
• Comfortable debugging distributed systems using logs and traces and familiar with OpenTelemetry basics
• Good collaboration and communication skills; experience with conversational UIs, prompt engineering, or security practices for AI systems is a plus
   

 

Preferred Qualification:

• Exposure to vector DBs/embeddings and RAG workflows

 

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.