Semble AI

We're building AI agents that design building-systems (fire, HVAC, plumbing, security) instantly and code-compliantly. The $600B building-system integration industry still runs on spreadsheets and manual drawings, even as building codes rapidly evolve and become more localized. It’s a massive blind spot for the tech world. We are transforming building-system design from a months-long, error-prone process into an instant, automated workflow. Semble AI is becoming the industry standard for top quality commercial building design. What you’ll work on As a founding engineer, you’ll work directly with the founders to own and build systems such as: Vision pipelines that segment rooms, walls, and architectural elements from noisy PDFs/CAD files LLM + RAG workflows that interpret building codes and produce compliant designs Full-stack features across our React/Node/Postgres platform You’ll have massive ownership and help set the technical direction of a company in a market that’s about to undergo a once-in-a-generation transition. Our tech Typescript / React / Node / Express / PostgreSQL Python (PyTorch, NumPy, etc.) Vision models: object detection, instance + semantic segmentation AI Agents: multi-agent reasoning, workflow orchestration, MCP RAG pipelines: vector DBs, embeddings, chunking strategies You might be a great fit if you Have strong experience in ML (vision AND LLMs), backend, building AI agents, and full-stack engineering Thrive in fast-moving environments and love shipping end-to-end Care about building reliable, production-grade AI systems Want to be early at a YC startup where your work directly defines the company’s trajectory Why join us You’ll work directly with the founding team (YC F25) Ship real AI systems into production for companies across the U.S. Own major pieces of the product and architecture Help shape the engineering culture from day zero Build something that will become the industry standard for top quality commercial building design