Founding Engineer (Full-Stack) – AI Agents

You've shipped agents people rely on, and you care about both the infrastructure and the interface. Be the first engineer next to the founders.

A profitable seed-stage startup in San Francisco, run by two founders, builds a platform that works like an internal workforce: AI agents take over whole tasks, such as accounts receivable via Slack or scheduling via email, and teams build their own internal apps on top. Customers so far came through referrals. You'll work across infrastructure and product: agent infrastructure, memory, recommendations, long-running agent execution, internal apps and the user experience. Your first focus is making the agents more useful and reliable, with hundreds of thousands of traces a week to learn from.

They're hiring 2 founding engineers.

What you'll own

• Agent infrastructure, memory and long-running execution
• The product layer: internal apps and a polished user experience
• Reliability, backed by evals you trust
• Broad ownership with no day-to-day micromanagement

Must-haves

• Solid infrastructure skills, and as a generalist you've shipped both product features and platform work
• Production software that runs reliably at scale, ideally agents users depend on, backed by evaluations you believe in
• A standout signal: a strong engineering team, founder experience or a founder fellowship, or a competitive achievement in maths, programming, debate or games
• You can explain every project on your CV in technical depth
• 1+ year of experience
• Working from the San Francisco office five days a week, 9-9-5

Bonus points

• Memory or long-running execution for agents
• Polished, detail-oriented UI and UX work
• Customer-facing experience (calls, onboarding or support)

What's in it for you

• $150k–$300k base + 0.1–2% real founding equity
• The first engineer next to the founders of a profitable company
• No hour tracking, unlimited AI budget and lunch every day
• Visa sponsorship available

Good to know

• Full-time, on-site in San Francisco, 9-9-5
• Process: founder conversation → technical deep dive on a project from your CV → a 2–4 day work trial or a 1–2 day take-home → references → offer

When you apply, please include

• Your CV (PDF), your LinkedIn URL, and GitHub or a portfolio if you have one
• An agent or AI workflow in production that people rely on, and the eval behind it
• Your current location, and confirmation that five days a week in San Francisco works for you
• Your visa or citizenship status
• Your base salary expectation, your notice period, and any other interview processes you're in

Does this sound like you? Apply now. If you're a match, we'll be in touch within 3 working days.

RnB Consultancy | Netherlands | 3604 AB Maarssen | KvK 71489703