Full Stack Engineer

Full Stack Software Engineer | Build AI-Powered Products at the Frontier of AI - San Francisco US Citizens only. Visa sponsorship is not available. We're looking for a talented Full Stack Software Engineer to join our lean, high-performing engineering team building the next generation of AI products. You'll work across the entire stack to build the applications, services, and infrastructure that power our World Engine —a digital environment where AI agents learn, reason, and interact with realistic software simulations. This is an opportunity to solve challenging engineering problems while shipping features that directly influence the future of agentic AI. What You'll Do Design, build, and ship full-stack features from concept to production. Develop scalable frontend applications using React and TypeScript alongside backend services in Python. Build and integrate software "replicas" into our World Engine, creating realistic environments for AI agents to interact with. Develop APIs, real-time services, and data pipelines that keep our simulated world accurate and responsive. Work on complex engineering challenges involving distributed systems, data consistency, and real-time interactions. Collaborate closely with AI researchers and product teams to rapidly prototype and deliver new capabilities. Write clean, well-tested, maintainable code and contribute to architecture and technical decisions. Tech Stack Frontend: React, TypeScript, Next.js, Vite Backend: Python, FastAPI, SQL, WebSockets Infrastructure & Tooling: Docker, Nx, Bazel, Playwright, Jest, Vitest, pytest What We're Looking For Must Have Bachelor's degree in Computer Science or a related discipline from a leading university. 2+ years of professional full-stack software engineering experience. Strong commercial experience with TypeScript, React, and Python . Experience designing, building, and shipping user-facing applications from end to end. Strong understanding of APIs, databases, software architecture, and modern engineering best practices. Experience working in a fast-paced startup or high-performing engineering environment. Nice to Have Experience building AI or LLM-powered applications. Experience with real-time systems, WebSockets, distributed systems, or event-driven architectures. Experience working at an AI-first startup or top-tier technology company. Why Join? Build products at the cutting edge of AI rather than maintaining legacy systems. Own features from idea through to deployment and production. Work across the full stack with modern technologies. Collaborate directly with world-class AI researchers. Join a small engineering team where you'll have significant ownership, autonomy, and impact from day one.