Our client, a leading technology business specialising in cybersecurity and penetration testing, is seeking an AI Software Engineer to join its permanent, fully remote team in the UK. This senior-level role focuses on building intelligent AI agents that can plan, reason, operate security tooling and identify exploitable vulnerabilities within controlled environments.

• Design, build and deploy AI agents that automate penetration testing, including planning, tool use and reasoning over security findings
• Develop sandboxed cyber-lab and range infrastructure using containers and Kubernetes
• Deliver AI features from initial design through to production, including evaluations, guardrails and monitoring
• Improve agent performance through prompt engineering, tool orchestration, evaluation and token and cost optimisation
• Integrate security tools and enable agents to operate safely within defined scopes
• Work closely with security researchers to translate offensive security techniques into effective agent behaviours
• Lead code reviews and technical design sessions while supporting the development of other engineers
• Contribute to reliable, scalable production systems across a polyglot technology environment

• Significant software engineering experience, with a proven ability to build and scale production systems
• Strong Python development skills and willingness to work with or learn Go
• Hands-on experience building and operating production AI applications using large language models and agentic frameworks
• Understanding of RAG, MCP, LangGraph or similar technologies, including tool integration and prompt design
• Experience creating reliable AI agents through evaluation, guardrails and token and cost optimisation
• Proficiency with Docker, Kubernetes and isolated sandbox environments, with cloud experience; GCP is advantageous
• Knowledge of microservices, gRPC, API design, asynchronous messaging and platforms such as Pub/Sub or Kafka
• Strong testing, communication and collaboration skills, alongside a genuine interest in understanding how systems are compromised

• Experience in offensive security, penetration testing, red teaming, capture-the-flag competitions or security tooling
• Experience driving security tools programmatically or automating an attack chain
• Experience working in a start-up environment with broad responsibilities and changing priorities

This is a remote position based in the UK. Due to the nature of the work, the role is open to UK citizens only and may be subject to nationality, residency and security-clearance checks.
If you are an AI Software Engineer with strong Python, AI and cybersecurity interests, this is an opportunity to work on autonomous security systems with a meaningful real-world impact. Apply now to take the next step in your career.