We're looking for a Lead Full Stack Software Engineer to create user-friendly, high-performing interfaces and frontend integration libraries that bring GenAI and intelligent automation capabilities to teams across IT, HR, Finance, Sales, Marketing, and Customer Support.

Responsibilities

- Architect and develop complete GenAI-powered applications, with a focus on intuitive web-based UIs and high-performing client-side API integrations
- Craft responsive, accessible frontend interfaces designed for streaming responses and minimal latency
- Construct and sustain a library of reusable frontend components, hooks, and design systems for enterprise-grade GenAI applications
- Bring LLM-based experiences to life using frameworks such as LangChain or LlamaIndex paired with OpenAI, Claude, or Gemini
- Partner with designers and product managers to quickly iterate on innovative AI UX patterns, including chat assistants, prompt builders, and feedback loops
- Guarantee security, accessibility, observability, and thorough test coverage throughout client-side and full-stack builds
- Produce responsive, accessible, and high-performance web UIs suited to AI-driven interactions like streaming text, prompt inputs, citations, and summaries
- Sustain a shared library of reusable frontend components and hooks so internal teams can easily integrate GenAI capabilities into their own applications
- Build UI components that offer transparency, observability, and trust in AI-generated outputs

Requirements

- 5+ years building production applications with React, TypeScript, or Vue for enterprise use cases




- 5–8 years of full-stack software engineering experience spanning frontend UIs, REST APIs, and microservices
- 2+ years integrating GenAI features, LLM APIs, and prompt UI patterns into web-based applications
- Solid Python backend skills, along with 2+ years building and consuming cloud microservices on AWS, Docker, and REST APIs
- Demonstrated track record building, documenting, and maintaining reusable component libraries, design systems, and custom hooks
- English proficiency at a B2+ level or higher

Nice to have

- Experience with real-time streaming UX patterns, including SSE/WebSockets, prompt builders, citations, and summary UI components
- Understanding of WCAG 2.1 AA compliance and how to architect accessible UI components
- Hands-on skills with client-side or Node.js LangChain, LangGraph, or LlamaIndex orchestration
- Exposure to RAG pipelines, vector search platforms like Pinecone or OpenSearch, and embedding fundamentals
- Experience with AI evaluation tools, feedback loop design, and interface-level guardrails

We offer

- International projects with top brands
- Work with integral teams of highly skilled, diverse peers
- Healthcare benefits
- Employee financial programs
- Paid time off and sick leave
- Upskilling, reskilling and certification courses
- Unlimited access to the LinkedIn Learning library and 22,000+ courses
- Global career opportunities
- Volunteer and community involvement opportunities
- EPAM Employee Groups
- Award-winning culture recognized by Glassdoor, Newsweek and LinkedIn

📌 Lead Full Stack Software Engineer (Argentina)
🏢 EPAM Systems
📍 Argentina