Senior Full Stack AI Developer (Python, FastAPI, Django, React.js, Next.js, LLM)

We are looking for an experienced Senior Full Stack AI Developer to enhance and extend an existing AI-powered web application. The ideal candidate should have strong expertise in both backend (Python/FastAPI/Django) and frontend (React.js/Next.js) development, along with hands-on experience integrating Large Language Models (LLMs) and AI technologies. This is not a greenfield project—you will work on an existing production application, implementing new features, improving existing functionality, and integrating advanced AI capabilities. Responsibilities Develop and integrate new AI-powered features into an existing web application. Build and maintain backend services using Python, FastAPI, and Django. Develop and enhance frontend features using React.js and Next.js. Integrate LLMs including OpenAI (ChatGPT), Anthropic Claude, and Google Gemini. Design and implement Retrieval-Augmented Generation (RAG) solutions using Vector Databases. Build AI assistants, chatbots, and intelligent automation workflows. Develop and maintain REST APIs. Optimize application performance, scalability, and security. Collaborate with the team to deliver high-quality, production-ready features. Debug, test, and improve the existing codebase. Required Skills Strong proficiency in Python FastAPI Django React.js Next.js Artificial Intelligence (AI) Machine Learning Large Language Models (LLMs) OpenAI (ChatGPT) API Anthropic Claude API Google Gemini API Vector Databases (Pinecone, Qdrant, Chroma, Weaviate, Milvus, etc.) REST API development Git Preferred Skills Retrieval-Augmented Generation (RAG) AI Agents Prompt Engineering LangChain or LlamaIndex PostgreSQL Redis Celery Docker AWS, GCP, or Azure CI/CD pipelines Qualifications 3+ years of professional experience with Python backend development. 2+ years of experience with React.js and Next.js. Experience building and integrating AI/LLM-powered applications. Experience working with existing production codebases. Strong understanding of scalable application architecture and API integrations. What You'll Build New AI-powered features and workflows. LLM integrations using ChatGPT, Claude, and Gemini. Semantic search and knowledge retrieval using vector databases. Modern React.js/Next.js user interfaces. Backend APIs and services for AI-powered functionality. Performance improvements and enhancements across the existing application. Nice to Have Experience with AI SaaS products. Experience integrating multiple AI providers in a single application. Familiarity with MCP (Model Context Protocol) servers and AI tooling. Experience with Supabase or Firebase. Understanding of authentication and authorization (JWT/OAuth). There is the possibility of more work if everything works well.