Onyx SecuritySenior Software Engineer
Tel Aviv, Israel · Full-time
Why join Onyx Security?
Picture every company's AI agents running under one control plane, where no rogue agent goes unseen, and Onyx Security is the one building it. The Wilmington cybersecurity software maker's $113M Series B is larger than 83% of Series B rounds from the last six months, and Bessemer, FirstMark and TCV are among its backers. With 14 open roles, 5 of them in sales, the company is still assembling its go-to-market team.
JustBacked's take, based on Onyx Security's own site and its funding and hiring data.
Description
Join Onyx Security and help build the control plane for autonomous AI in a fast-moving, high-impact environment. Onyx is building the control layer that enables enterprises to safely adopt and scale AI agents across the organization, with the visibility, governance, and operational control needed to understand what agents exist, what they do, how they behave, and what risks they introduce.
About the role
Onyx is looking for a Senior Software Engineer to help build the core of our AI security platform and AI Control Plane.
You will build systems that help enterprises understand, monitor, and control how AI agents and LLM-based applications operate across their organization. We expect engineers to work in an AI-native way: leveraging and orchestrating AI agents to accelerate design, implementation, testing, debugging, and iteration, while owning the quality of the final result.
This role requires strong ownership, system design judgment, and the ability to turn complex AI-security problems into reliable production systems.
What you will do
- Leverage and orchestrate AI agents and LLMs to design, build, test, debug, and ship core platform capabilities.
- Build systems for monitoring, governing, and controlling AI agents, LLM applications, tool usage, prompts, context, policies, and runtime behavior.
- Turn ambiguous AI-security problems into simple, scalable, production-grade systems.
- Own technical decisions from design through production, working closely with Product, Security, and Engineering.
Requirements
What you will bring
- 5+ years of backend software engineering experience in production environments.
- Strong system design skills and backend fundamentals: APIs, data modeling, scalability, performance, and reliability.
- Proven ability to own complex systems end to end, operate independently, and create clarity in ambiguous situations.
- Strong interest in AI, LLMs, agents, and the security challenges around their adoption.
- Clear communication and strong cross-functional collaboration skills.
Nice to Have
- Experience building production systems with LLMs, AI agents, or agent orchestration.
- Experience in cybersecurity, cloud security, or enterprise security products.