Junior AI Engineer - LLM & Security

About the role

CENSUS, a cybersecurity firm working with Fortune 500 companies, financial institutions and critical infrastructure, is looking for a Junior AI Engineer to join its AI team. You will own features in production AI systems end to end, from data and first measurements through evaluation, deployment and iteration, applying your machine learning experience to security-relevant AI. The position is fully remote in Europe.

Key responsibilities

• Design, build and ship LLM-based features together with the evaluations that prove they work.
• Own work on retrieval (RAG), agent and tool-routing systems that answer questions over real security data.
• Build datasets and fine-tune open models on security data, measuring results against a baseline.
• Scope your own tickets with your mentor and back every change with before-and-after results.
• Review teammates' pull requests and help guide interns.

Required profile

• At least 1 year of hands-on experience in AI, Machine Learning or Data Science engineering; internships and industry or research-lab work count.
• A track record of shipping at least one ML or LLM feature into production or another people's codebase.
• Open to graduates (Bachelor's, Master's or PhD) in Computer Science, AI, Machine Learning, Data Science or related fields, or candidates with equivalent practical experience.
• Europe-based candidates are prioritised.

Required skills

• Strong Python with readable, tested code.
• Experience in a team codebase: Git, pull requests and code review.
• Practical experience building and evaluating LLM applications (prompting, RAG or agents).
• Solid grasp of machine learning fundamentals and the ability to design experiments and read their results honestly.
• Working knowledge of SQL and Docker.
• Good written English; non-English resumes will be rejected.

What we offer

• Real ownership of features in production AI systems.
• A named AI-team mentor for the first months and code review on every pull request.
• Work alongside AI and cybersecurity experts on LLM features, RAG, agent systems, evaluations, datasets and fine-tuning.
• A clear path to AI Engineer as you take on larger, less defined work.