Senior Python AI Engineer
Willis Towers Watson5 days ago
London, United KingdomSenior
Responsibilities
- Design, develop, and maintain AI-powered application services using Python.
- Build agentic workflows and AI orchestration with LangGraph and LangChain.
- Develop scalable APIs and backend services using FastAPI.
- Design and implement RAG pipelines using vector, metadata, and graph-based retrieval.
- Integrate AI services with the HR Expert application and existing enterprise systems.
- Develop and deploy solutions on Microsoft Azure across relational, document, vector, and graph-based data stores.
- Contribute to multi-agent AI workflows involving tools and multiple data sources.
- Participate in technical design, code reviews, architecture decisions, testing, observability, performance, and maintainability practices.
- Evaluate emerging AI technologies and occasionally contribute to frontend or existing .NET services.
Requirements
- Strong production Python development experience.
- Experience building APIs and backend services, ideally with FastAPI.
- Proven experience building LLM-based applications with LangChain and/or LangGraph and agentic workflows.
- Experience developing RAG solutions and integrating systems and data sources.
- Knowledge of production generative AI challenges including retrieval quality, grounding, context management, evaluation, reliability, and performance.
- Experience with automated testing, source control, code review, and production-quality engineering practices.
- Valuable experience includes complex RAG architectures, hybrid search, reranking, agent-driven retrieval, graph databases, GraphRAG, ArangoDB, Azure AI services, vector or semantic search, Docker, Kubernetes, multi-tenant applications, LLM evaluation, observability, Angular, NgRx, or .NET/C#.
Benefits
- 25 days of annual leave plus an additional WTW day.
- Private healthcare, life insurance, group income protection, and regular health assessments.
- Defined contribution pension scheme with company-matched contributions up to 10%.
- Hybrid working options, an employee assistance programme, and a fully paid volunteer day.
- Optional electric vehicle car scheme, share scheme, cycle-to-work programme, dental and optical cover, and critical illness protection.
Tech Stack
Categories
About Willis Towers Watson
WTW is a global advisory, broking, and software firm serving employers, insurers, and institutional clients across people, risk, and capital. It provides insurance brokerage and risk advisory, employee benefits and pensions consulting, and HR/benefits administration software and analytics. Headquartered in London and listed on NASDAQ (WTW), the company was formed in 2016 via the Willis Group–Towers Watson merger and operates in roughly 140 markets worldwide.