Founding Engineer (AI Infrastructure Startup)

About the role

This is the first engineering hire at a freshly funded pre‑seed startup building the infrastructure layer for AI‑native service businesses. You will work directly with the solo founder to turn a live, revenue‑generating product into agentic infrastructure capable of serving a million users. If you are the right person, this role grows into a CTO seat, with the title following the work.

Key responsibilities

• Rebuild a working product into scalable agentic infrastructure, owning the architecture end to end.
• Design and operate the agent runtime: orchestration, memory, verification, and the systems that make an AI workforce reliable.
• Own the full stack, backend, infrastructure, frontend, and agent systems, taking work wherever the company needs it next.
• Set the technical bar, the stack, and the engineering culture as the person who defines them first.
• Ship to production users on a weekly cadence, with real businesses depending on what you build.

Required profile

• At least 2 years shipping production software, or an equivalent track record as a founder or solo builder.
• Demonstrated experience building and running LLM or AI agent systems in production with real users.
• Full‑stack range: able to take work from backend and infrastructure through to the UI without waiting for a specialist.
• Proven ability to turn a working prototype into infrastructure that holds real load, covering architecture, data modelling, runtime, and orchestration.
• Experience owning technical decisions with no engineering organisation above you, as a founder, early hire, or solo technical lead.
• Founder instincts; ex‑founders are a strong signal.
• Familiarity with agent orchestration, agent memory, evals or verification systems, or multi‑agent workflows is a strong plus.
• Based in the San Francisco Bay Area, or genuinely open to relocating there.

What we offer

• Base salary: $150,000 to $250,000 USD annually, with a wide band to let the right person set their own number.
• Meaningful founding equity is included.
• Relocation support and visa sponsorship are genuinely available for candidates not yet in the US.