About the job
Why Join Us
At Brex, we are revolutionizing corporate spending with our AI-driven platform. We empower businesses to manage their expenses confidently through integrated corporate cards, banking services, and global payment solutions, complemented by intuitive software for travel and expense management. From startups to established enterprises like DoorDash, Flexport, and Compass, thousands of companies rely on Brex to control spending proactively, reduce costs, and enhance efficiency on a global scale.
Joining Brex means pushing your limits, questioning the status quo, and collaborating with some of the industry’s brightest minds. We are dedicated to fostering a diverse team and an inclusive culture, believing that your potential should only be limited by your dreams. We empower you with the tools, resources, and support needed to advance your career.
AI at Brex
Our AI Engineering team is redefining finance management by embedding intelligent, autonomous systems into the Brex platform. We develop AI agents that not only provide insights but also take action to optimize spending, manage workflows, and make real-time decisions for our customers. By integrating proprietary financial data with our product and platform infrastructure, we simplify complex financial operations into seamless, automated experiences, setting a new standard for modern finance.
What You’ll Do
As a Senior Software Engineer, you will be responsible for Brex’s simulation and validation platform for AI-driven products. Your primary goal is to ensure that every AI interface at Brex is rigorously tested under realistic conditions, enabling teams to deploy with confidence.
You will design a system that leverages synthetic data and scenario generation to create a recursive self-improvement loop. Product teams will depend on this platform to detect regressions proactively, validate new features safely, and continuously refine prompts and agent behaviors. This platform will operate within isolated, ephemeral environments closely resembling production.
This is not a research position; it involves actively engaging with real products, creatively breaking them to foster organizational improvement.
Where You’ll Work
This position is based in our San Francisco office. We offer a hybrid work environment that blends the energy of in-office collaboration with the flexibility of remote work. We require team members to be in the office three days a week—Monday, Wednesday, and Thursday—while also allowing up to four weeks of fully remote work each year!

