Founding AI Engineer

Semble AI; San Francisco (CA); On-site; USD 120,000 - 150,000; Full time

Job summary

Semble AI is looking for a Founding Engineer to help revolutionize the building-systems design industry. You will work closely with the founding team to build AI agents that design systems such as fire, HVAC, plumbing, and security, transforming a traditionally manual process into an automated workflow.

Preferred candidates will have experience in ML, backend, and full-stack engineering. Join an innovative startup, shape its technical direction, and make a significant impact in the market.

Qualifications

• Strong experience in ML (vision and LLMs), backend, and full-stack engineering.
• Experience in building reliable, production-grade AI systems.
• Ability to thrive in fast-moving environments.

Responsibilities

• Work directly with founders to build vision pipelines from PDFs/CAD files.
• Create compliance systems for building codes using LLM + RAG workflows.
• Develop full-stack features across the platform.

Skills

Machine Learning (ML)

Full-stack Engineering

Backend Development

AI Agents

Typescript

React

Node

PostgreSQL

Python

Job 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