Source description
About the role
Founding Product Engineer (AI Agents, Full Stack)
Level: Senior / Founding IC (2 hires)
Location: San Francisco — Hybrid 3–4 days onsite
Tech: Python, React
Focus: AI agents (not RAG/chatbots)
INDUSTRY: Client builds AI coworkers that handle operational tasks for enterprise teams — not chatbots but actual colleagues you can delegate work to. They're working with top AI companies and fast-moving startups as design partners.
The Role
We're building the founding engineering team — the people who will define how this company is built, technically and culturally, from day one.
There is no product playbook for what we're building. The questions you'll be answering are ones the industry hasn't answered yet: How do you design an agent system that reliably replaces a human workflow, not just assists one? How do you orchestrate multi-step autonomous processes that hold state, adapt to context, and act without a human in the loop? How do you make that trustworthy enough that a company hands you their entire sales org?
Today, you're writing code alongside the founders. In two years, you're leading a team and owning product surfaces that run critical operations at real companies. The decisions this team makes in the next 12 months will define the architecture, the culture, and the category.
What You'll Build
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The core Agentic Process Engine — the system that runs business units, not individual tasks
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Starting with sales: the agent layer that handles post-call briefs, follow-ups, pipeline hygiene, win wires, and proactive deal risk detection — autonomously
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The full stack: frontend, backend, orchestration infrastructure
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The architecture for how agents coordinate across integrations, hold memory over time, and take action reliably
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The foundation for a technical team you'll eventually hire and lead
Who You Are
5–10 years of engineering experience
You've shipped real AI agent systems — tool use, multi-step reasoning, memory, autonomy.
You understand the hard parts: hallucination, state drift, over-triggering, trust collapse at scale. And you've figured out how to engineer around them.
You've done early-stage startup work — high ambiguity, no spec, no PM, no one to tell you what's next. You've made something out of nothing.
Opinionated. You have strong views on how systems should be built. You push back when something doesn't make sense.
Strong across the stack. Backend, frontend, whatever it takes.
You have a strong network of engineers you'd want to work with again. We want our first hires to hire our second — and so on.
Based in San Francisco or willing to relocate.
Extra Credit
You've replaced a business process with AI — not augmented it. Owned the outcome.
Deep integrations with GTM tools: Salesforce, Gong, Outreach, Slack, Google Workspace
Workflow orchestration or event-driven systems at scale
You've thought hard about human-in-the-loop design: when agents act, when they escalate, when they stop
Are a past founder or founding engineer
What You Get
Founding equity, competitive salary
The chance to work on a problem that genuinely hasn't been solved
Architecture, culture, and team decisions that are yours to make
A small team moving fast, with the backing to do it right
Seniority
5 - 7 years of experience in full- stack software engineering at a product- first company (e. g. Notion, Linear)
Work experience
Experience building AI agents, not just RAG/chatbots
Experience shipping 0- to- 1 products with clear business impact
Experience at a VC- backed startup
Education
Undergrad in CS
Hard skills
Proficient across the stack, team uses Python and React
Soft skills
High agency and opinionated on product and code
Traits to avoid
Candidates who are purely frontend or backend
Experience only at large, slow- moving enterprise companies e. g. JP Morgan or SAP
Managers with no recent hands- on coding experience
Interview Process
Quick, informal Teams meeting with Kelly/Excel
Founder interview — product, agency, background
Founder technical interview
Paid 1‑day work trial
More at 3B Staffing