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Mason are hiring a Founding Engineer - Data

Mid-level San Francisco, California, United States Visa sponsorship posted 2026-10-09

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Mason - Accelerating development of the built world

Mason is on a mission to accelerate the development of the built world. We are tackling some of the most pressing challenges of our time - housing shortages, energy constraints, and decaying infrastructure - all of which are exacerbated by the slow pace of physical development.

This is one of the largest, least-modernized markets in the world. Trillions in spending, and much of the work still runs on spreadsheets, documents, and manual processes.

We create AI systems that transform some of the largest firms in the world.

A core part of this work is building the company brain: turning decades of fragmented documents, databases, emails, and operational knowledge into connected data and context that AI agents can actually use.

We're growing fast - we have an 8-figure pipeline of projects and are looking for great engineers to join our team.

Our founding team comprises a repeat founder who exited to a Fortune 500, a former tech lead at Meta Superintelligence who co-created Meta AI, and a development director who built $2B+ of projects.

The Role

You'll be the person who turns a company's fragmented information into a company brain that AI agents can trust. You'll design and build the backend systems that ingest, organize, connect, and retrieve decades of enterprise knowledge.

The hard part goes well beyond moving data from one place to another. A property might have different names across systems. Documents can contradict one another. Important context can sit in a spreadsheet, a drawing, or an email thread. You'll figure out how to preserve those relationships and give an agent the right information for the task in front of it.

This role combines backend engineering, data architecture, and experimentation. You'll work closely with our CTO and the Infrastructure and Deployment engineers. You'll own production pipelines and processing infrastructure, with particular depth in data modeling, reconciliation, retrieval, and context quality.

What you'll build

Tech stack and tools

Relevant experience includes:

We value experience building production systems with these or comparable technologies.

What we're looking for

Team and culture

If you want to help redefine the built world - let's talk :)

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