Head of Engineering Onsite NY; San Francisco, CA)

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.

You'll lead engineering at Mason while continuing to build. You'll work directly with our CTO to make technical decisions, drive delivery, and help a small team take on increasingly complex enterprise AI deployments.

Initially, expect roughly 70–80% hands-on engineering and 20–30% leadership. You'll write and review code, design systems, and solve difficult implementation problems. You'll also set priorities, surface risks early, give direct feedback, and help engineers deliver work they can stand behind. The balance will evolve as the team grows.

You may already be a technical lead manager, an engineering leader, a staff engineer, or a former founder. What matters is recent technical depth and evidence that you've helped a group of engineers deliver something substantial.

• Build and review the backend, data, and AI systems that power enterprise deployments

• Own engineering architecture and make sound system-design, vendor, and build-versus-buy decisions

• Translate company and customer priorities into clear engineering goals, plans, and ownership

• Keep delivery moving across projects, identify risks early, and resolve technical or organizational blockers

• Coach engineers, give candid feedback, and hold people accountable for outcomes

• Set practical standards for correctness, security, testing, observability, and operating production systems

• Work with the deployment team to make customer commitments realistic and turn repeated needs into shared infrastructure

• Help hire and develop the team as our engineering needs grow

• Substantial recent experience designing, building, and operating production software, grounded in at least four years of engineering work

• Demonstrated leadership of engineers or a substantial technical initiative involving multiple contributors

• Strong system-design judgment and the ability to get into code and implementation details

• Evidence of setting priorities, making tradeoffs, and delivering through uncertainty

• The ability to give direct feedback, handle difficult conversations, and improve the effectiveness of the team

• Clear communication with founders, engineers, and customer stakeholders

• High ownership and the ability to run engineering work independently

You might bring:

• Technical depth: strong architecture and engineering judgment in backend, data, infrastructure, or production AI systems

• Team leadership: a record of making engineers more effective and holding a high standard for delivery

• Founder experience: building from an unclear starting point, making consequential decisions, and owning the result

• Enterprise delivery: experience translating…