- Salary
- $150k – $250k/yr
- Location
- San Francisco, California, US
- Type
- Full-time
- Department
- Engineering
- Source
- Y Combinator
Description
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
