Senior Software Engineer

About the ClientOur client is an early stage technology company operating at the intersection of AI and cybersecurity.The company is building an AI driven security platform focused on autonomous security testing, using AI agents to identify vulnerabilities and assess systems dynamically.The engineering team is small, giving senior engineers significant ownership and influence over architecture, engineering practices and the evolution of the product.About the RoleThis is a hands on role for an experienced Software Engineer who enjoys solving complex technical problems, working across different areas of engineering and taking ideas through to production.You will work across backend engineering, distributed systems, cloud infrastructure and AI native development, with the opportunity to contribute directly to the architecture and technical direction of the platform.What You’ll Do

• Design, build and evolve backend services and production systems using Python.
• Work with distributed systems, concurrent workloads and cloud infrastructure, particularly AWS.
• Build and maintain infrastructure using Terraform and Infrastructure as Code.
• Develop reliable, scalable and secure systems and contribute to their operation in production.
• Contribute to AI native development, AI agents and agentic workflows.
• Work on evaluation, observability and traceability of AI driven systems.
• Contribute to system architecture, technical standards and engineering practices.
• Work closely with product and engineering teams to turn complex problems into practical solutions.What You’ll Bring
• Strong professional experience building software, particularly backend systems.
• Strong Python engineering skills.
• Solid SQL and experience with relational databases.
• Proven experience building and operating real production systems.
• Experience with cloud infrastructure, containers and Infrastructure as Code.
• Experience with AWS and Terraform.
• Experience working with distributed systems, concurrent workloads or long running systems.
• A strong security mindset, including areas such as authorisation, secrets, isolation and threat modelling.
• Practical experience with AI assisted or AI native software development, ideally including AI agents or LLM workflows.
• Strong technical judgement, problem solving skills and the ability to take ownership of complex engineering challenges.
• Comfortable working autonomously in an early stage environment.Particularly ValuableExperience with any of the following would be particularly valuable:
• AI agents and multi agent orchestration
• AI evaluation, observability and traceability
• Cybersecurity, security engineering or security research
• Offensive security, penetration testing, bug bounty or CTFs
• Grafana or other production observability tooling
• Node.js, TypeScript, React or Next.js
• Distributed workflow or durable execution systems
• Multi tenant SaaS platforms
• Scaling or re platforming live production systems
• Founding or early stage engineering experienceYou do not need to match every requirement. Strong technical breadth, excellent problem solving skills and a proven ability to take ownership of complex production systems are particularly valued.

Location: London, with 3 days per week in the office.By submitting your application, you agree to the processing of your personal data in accordance with our Privacy Policy.