Software Engineer

About RunSybil

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.

About this Role

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.

What You'll Do:

• 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
  

We're looking for someone who brings:

• 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
  

Location: Hybrid role based in New York City. Some travel may be required.

Diverse teams build better products. RunSybil is committed to hiring people who bring different perspectives, lived experiences, and backgrounds to our work. We encourage candidates of all races, ethnicities, gender identity and expression, sexual orientation, disability or medical conditions, ages, religions, and socioeconomic backgrounds to apply. Pursuant to the San Francisco Fair Chance Ordinance, we will consider for employment qualified applicants with arrest and conviction records. If you're excited about this role but don't check every box, we still want to hear from you.