Founding Engineer

Ploy; San Francisco (CA); On-site; USD 140,000 - 210,000; Full time

Job summary

Ploy is building an agentic marketing platform in San Francisco. We deploy swarms of marketing and web design agents that monitor websites and proactively launch campaigns, content, and optimizations, providing growth engine capabilities for companies.

We seek engineers excited to own end-to-end systems, from frontend to ML/agent infra, with production experience in LLMs. This is a hands-on, in-person role with a small, senior team that moves quickly.

Qualifications

• Built something from 0 to 1 and thrives in ambiguity.
• Comfortable diving deep in stack areas: frontend, backend, infra, or ML/agent systems.
• Experience with LLMs in production, or eager to learn.
• Decisive with incomplete information and honest about issues.
• Wants to work in person in San Francisco with a small, fast-moving team.

Responsibilities

• Build multi-agent systems that plan, execute, and learn from websites and growth channels in production.
• Develop infrastructure to let agents make changes to live sites safely at scale (previews, diffs, rollbacks, performance guardrails).
• Create primitives and interfaces customers use to direct agents themselves.
• Implement feedback loops to make the product smarter the longer it runs.

Skills

End-to-end product development

Ambiguity navigation

ML/Agent systems

Production ML experience

Job description

About Ploy

Ploy is an agentic marketing platform that turns your website into your company's main growth engine. We deploy swarms of marketing and web design agents that monitor your site and proactively launch campaigns, content, and optimizations — giving companies the on‑demand infrastructure of a growth team. Ploy is founded by Bryant Chou, the co‑founder and former CTO of Webflow, where he spent 12+ years building the core product, CMS, and hosting that now power ~1.5% of the internet. We're a small, senior team based in San Francisco and backed by Y Combinator and other Tier 1 investors.

What you'll work on

• Multi‑agent systems that plan, execute, and learn from websites and growth channels in production — orchestration, memory, evals, and everything it takes to keep them reliable.
• The infrastructure that lets those agents make changes to live sites safely at scale — previews, diffs, rollbacks, performance guardrails.
• The primitives and interfaces customers use to direct the agents themselves.
• The feedback loops that make the product get smarter about a customer's business the longer it runs.

Who we're looking for

• You've built something from 0 to 1 and thrive in ambiguity.
• You're comfortable going deep on any part of the stack — frontend, backend, infra, or ML/agent systems — and have strong taste in at least one.
• You've worked with LLMs in production, or you're hungry to.
• You make good decisions fast with incomplete information, and you're honest when something isn't working.
• You want to work in person in San Francisco, most days, with a small team that moves quickly.

If you don't match this exactly but think you'd be great here, apply anyway. We read everything.