Software Engineer

RunSybil•New York City, NY

5d•Hybrid

About The Position

RunSybil is an AI security startup scaling offensive security services by automating hacker intuition. We're building Sybil: an AI-powered penetration testing product that finds vulnerabilities faster than human hackers. Backed by strong investor support and early customer traction, our team is composed of experts from the likes of OpenAI, Meta, Mandiant, Palantir, Cruise, and Trail of Bits. Building Sybil means working on hard problems at the intersection of AI and offensive security. This is a role for engineers who want real ownership over what they ship and care about the quality of what they build. The engineers who thrive here move quickly on ambiguous problems, build infrastructure that scales, and care deeply about the quality of what they ship.

Requirements

6+ years building products or platforms that serve real customers
Strong foundation in distributed systems, including how they fail and how to recover
Experience as a core contributor on a team that scaled a product to meet significantly increased demand
Proficiency with Python and TypeScript; comfort working across the stack when needed
Familiarity with cloud platforms (AWS, GCP, or Azure), containerization, and modern deployment practices
Deep understanding of how to apply modern AI and LLMs for real product impact
Experience with observability tooling and a track record of debugging hard problems in production
An interest in or background in security, penetration testing, or offensive security tooling
A track record of picking up what needs to be done and doing it, without needing a defined lane
Strong communication skills: you can explain technical tradeoffs clearly to teammates and collaborators

Responsibilities

Design, build, and ship secure, scalable systems that power automated penetration testing at scale
Own features end-to-end: from technical design through deployment and production monitoring
Identify gaps in the product and propose technical initiatives to close them, without waiting to be asked
Lead technical design discussions and contribute meaningfully to decisions on architecture, tooling, and approach
Translate ambiguous challenges into clear plans and execute them in close collaboration with the team
Scale backend systems and data infrastructure to stay ahead of growing customer demand
Integrate and extend AI and LLM capabilities, including agents and agentic workflows, directly into the Sybil product
Take ownership of reliability and performance, including when things break and how to recover
Set and uphold high standards for code quality, craftsmanship, and engineering culture as we grow