AI Engineer, Product

We are looking for an AI Engineer (Product) with 1–8 years of experience to join Build's founding engineering team and own the full-stack, user-facing layer of an agentic AI platform built for institutional real estate. You'll be a product-minded engineer who ships production software to real customers — not demos — and has the curiosity and ownership mentality to thrive in a fast-moving, high-trust seed-stage environment.

What will you be doing?

• Build and iterate on the customer-facing web app, owning full-stack features end-to-end from backend workflow logic to user-facing surfaces
• Design and ship agentic workflows that help real estate teams automate complex workflows (site sourcing, diligence, acquisitions) using frameworks like LangGraph or LangChain
• Work with geospatial-heavy product surfaces — maps, layers, performance — and have strong opinions on how to make them fast and reliable
• Collaborate directly with domain experts and internal users (the team uses its own product daily) to translate messy real-world workflows into clean product experiences
• Own the BFF (backend-for-frontend) layer and data modeling to ensure the backend serves the frontend cleanly and efficiently

Key Requirements

• TypeScript-first — strong opinions on frontend frameworks (React, Svelte, SolidJS) and JS runtimes (Node, Bun, Vite); can defend choices with reasoning, not just name-dropping
• Has shipped production full-stack features to real external users — not internal tools or prototypes; genuine end-to-end ownership of a significant product surface
• Hands-on experience with agentic AI frameworks (LangGraph, LangChain, or similar) in production, not just experimentation
• High agency, high ownership mentality — comfortable with broad scope, ambiguity, and startup intensity; not looking for a narrowly scoped 9-to-5 role
• Fully on-site 5 days/week — New York now, transitioning to San Francisco this summer; must be local or willing to relocate