AI Fullstack (Python focused) Engineer

You will be cooperating with a leading provider of AI evaluation and optimization solutions, trusted by multinational companies to optimize AI agents and detect performance issues in large language models.

• Ability to work 2:00 p.m. - 10:00 p.m. (CEST)
• Proven experience in building and maintaining production-ready agentic systems (custom evaluation harnesses)
• Solid understanding of how modern LLMs work at the API level, including tool calling, agent loops, context management
• 5+ years experience as a software engineer, full stack engineer, or similar
• Experience with Java, Python, and backend frameworks like FastAPI or Django
• Strong experience building production software with TypeScript
• Strong experience designing APIs, services, data models, and workflows — ideally with TypeScript, Python, FastAPI, Java, and Postgres

Nice to have:

• BS/MS in Computer Science, Mathematics, Statistics, or a related quantitative field
• Experience with Next.js and Material UI
• Experience with cloud environments like AWS
• Familiarity with vector and columnar databases

• Build RL environments end-to-end: frontend interfaces, backend services, APIs, data models, and workflows using technologies like TypeScript, Python/FastAPI, Java, and Postgres
• Build tooling and shared services, including agentic systems and frontends for trajectory review, verifier debugging, and reward hacking checks
• Work with AI coding tools (Claude Code, Codex, and similar) to generate ideas for extending and building new tooling
• Design efficient data models and REST APIs
• Develop internal tools and libraries (e.g., a data visualization library) to improve productivity across the engineering team

Due to the client’s time zone, candidates who can work until 10:00 p.m. CEST are preferred.