AI Security Researcher/Research Engineer (AI Security)

Location: London, England preferred; exceptional candidates in the rest of Europe may be considered. Remote or hybrid.

Company

A privacy-focused technology startup building a web browser, private search engine, private AI assistant, and privacy-preserving advertising network.

What you will do

• Design and execute adversarial evaluations for LLM-powered web agents and chatbots, including prompt injection, tool abuse, and data exfiltration scenarios.
• Analyze model behavior and internal reasoning to understand and forecast security risks in frontier models.
• Develop and prototype security-focused training and fine-tuning techniques.
• Integrate information flow control, privilege control, and contextual security principles into web agents.
• Collaborate with engineering, privacy, machine learning, and cryptography researchers to convert findings into product changes, tests, and measurable improvements.
• Help define security strategy and responsible-release policies for web agents.

Requirements

• Demonstrated experience with secure AI, including prompt injection attacks and security guardrails.
• Strong publication record in AI security, ML security, or a closely related field.
• Strong Python coding skills and familiarity with PyTorch or JAX.
• Experience training, fine-tuning, and evaluating large language models.
• Deep familiarity with large language models, web agents, and their training processes.
• Experience applying information flow control, access control, or least-privilege principles.

Nice to have

• Ph.D. in computer science, with exceptions considered for relevant industry experience.
• Experience shipping products and features in a fast-moving environment.
• Open-source security or privacy projects.
• Experience with confidential computing and ZKP/SMPC protocols.
• Publication record in premier systems, performance, or machine learning venues.

Culture & Benefits

• Work with cutting-edge AI, privacy, and security technologies.
• International startup environment with exposure to a global team.
• Competitive compensation and opportunities for personal growth.
• Remote or hybrid work options, with London as the preferred hiring location.