Build the future of offensive security with XBOW. Attackers are already using AI to move faster than defenders can react—we’re creating the platform that puts security ahead in the arms race. Our AI-powered system autonomously discovers, validates, and even exploits vulnerabilities, giving organizations proof-backed results in hours instead of weeks.
Founded by Oege de Moor, creator of GitHub Copilot, and backed by Sequoia, Altimeter, and other leading investors, XBOW is applying cutting-edge AI to one of the world’s most urgent problems. In just over a year, our AI, built by a world-class AI team and legendary security researchers — has uncovered thousands of real-world zero-days across the software billions rely on, and achieved the #1 ranking on HackerOne’s global leaderboard.
We’re a team of builders, hackers, and researchers who thrive on solving problems others think are impossible. If you want to push the boundaries of AI, reshape how security is done, and join the group defining this new era of defense — we’d love to talk.
Your Role
We’re looking for a Software Engineer who’s passionate about building reliable and high quality products with robust backend systems. In this role, you’ll design and implement end-to-end features across the stack: from React-based frontends and TypeScript APIs to backend services in Kotlin and Go, all deployed on AWS.
You’ll be joining a small team of superstars that’s shipping quickly and operating with high trust. This is a role for someone who loves to own open-ended problems and figure things out—whether that’s designing seamless API contracts, optimizing database interactions, or building scalable systems that make powerful AI capabilities accessible. If you like being at the intersection of deep tech and real-world impact, you’ll feel right at home.
What You’ll Do
Design and build full-stack systems that integrate frontend and backend seamlessly
Develop scalable APIs and backend services in TypeScript, Kotlin, and Go
Deploy and operate services in AWS and other cloud providers
Own problems end-to-end—from design through deployment to production support
Navigate ambiguity and help define how we build as much as what we build
Collaborate closely with teammates across the stack, including AI researchers, Security researchers and backend engineers
Who You Are
Experience building and operating full-stack systems
Proficiency with TypeScript
Experience designing and consuming APIs (REST or GraphQL)
Strong backend development experience (Node.js, Kotlin, Go, or similar languages)
Strong problem-solving skills and the ability to work with incomplete information
A thoughtful communicator who values clarity and simplicity
Comfort working in a fast-paced, early-stage startup environment
Bonus If You Have
Experience with event-driven architectures, message queues, or async workflows
Experience building scrappy, iterative frontends where speed and feedback loops matter more than polish
Familiarity with AWS or similar cloud platforms
Comfort working with infrastructure as code (e.g., Terraform or CDK)
A strong appreciation for user experience and design, even if you’re not a formal designer — you care about how features feel as much as how they work
Comfortable prototyping quickly in React/TypeScript and turning ideas into working features fast
Experience designing and optimizing relational databases (we use Postgres), and you know how to structure data for both performance and clarity.
Background in systems programming, networking, or performance tuning
Experience with hybrid deployments (cloud + on-prem) and know how to build resilient systems that handle the complexity of mixed environments.
Experience working in an early stage startup
Prior experience building security products or products for technical users
What We Offer
Compensation & Equity: Competitive salary and a generous equity package, making you a true owner of the company.
Career Growth: Shape your role, lead the function, and grow with the company as we redefine cybersecurity.
Meaningful Work: You will tackle technically complex challenges and play a pivotal role in the growth of our business, working alongside an amazing team and some of the world’s experts to shape how AI transforms cybersecurity.
What Else You Should Know
We aren’t focused on seniority titles at XBOW—so if you’re worried about “leveling,” don’t be. We care a lot more about mission fit, capability, and impact than what’s on your LinkedIn headline.
We believe in people who are driven by curiosity and a willingness to learn. Even if you don’t check every box, we encourage you to apply if you’re excited about the role and our mission.
