Lemma

Production Monitoring for AI agents

Product Designer

$140K - $190K0.50% - 1.00%San Francisco, CA, US
Job type
Full-time
Role
Design, Product design
Experience
Any (new grads ok)
Visa
US citizen/visa only
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Jerry Zhang
Jerry Zhang
CEO

About the role

Lemma reads all of your agent conversations, finds the failures nobody knew to look for, and opens the PR that fixes them.

Why this role exists

Our product's job is to make an engineer trust a fix they didn't write.

That's a design problem more than a technical one. Someone has to look at a surfaced failure and understand in about four seconds what broke, how often, who it hit, and whether our proposed patch is right. If that takes forty seconds instead, they close the tab and go back to grepping logs.

So the surface area here is dense and unglamorous. Trace timelines, diff views, evidence chains, nested detail states, tables that have to stay readable at ten thousand rows. This is not a marketing site job. If you want to make beautiful things, there are easier products to make beautiful.

You'd be the first designer here, which means you're setting the system, not applying one.

What you'll do

  • Own the product surface end to end: detection review, trace exploration, the PR review flow that decides whether we get trusted
  • Build the design system from nothing, and keep it alive as the product changes under it weekly
  • Ship your own work. You'll be in the codebase, not handing off Figma files
  • Sit in on customer calls and watch real engineers use this. The gap between what they say and what they do is where the work is
  • Make the hard call about what not to show. Most of this product is about hiding 99% of the data well

What we're looking for

  • 3+ years designing software, with real examples of complex, data-dense interfaces. Consumer polish alone won't transfer here
  • You write code. React and TypeScript, well enough to ship your own work to production
  • You've designed for engineers before, or you are one. Knowing what a trace is and why a diff view is hard saves us months
  • Taste you can defend. We'd rather hear why you cut something than why you added it
  • Comfortable with ambiguity. Nobody here will hand you a spec, and the product changes weekly

We move fast on hiring. Target is an offer within two weeks of first contact.

Onsite in San Francisco. We sponsor visas.

About the interview

We keep this short on purpose. Target is an offer within two weeks of first contact.

Intro call with a founder (30 minutes). What we're building, what you've built, whether the shape of the role fits what you want next.

Take-home project and review. A real design problem from Lemma, not an invented one. You work on it on your own time, then we go through it together. The conversation matters more to us than the artifact.

Paid work trial (2 days, onsite). Real problem, real codebase, sitting with the team, paid at market rate. You find out what working here actually feels like before you commit.

About Lemma

Lemma is a YC F25 company building production monitoring for AI agents. We help companies automatically improve their AI agents from production data by catching the silent failures your observability tools miss and building self-healing loops.

We're backed by Y Combinator, Matrix, Liquid 2 and operators from OpenAI, xAI, and Doordash. We look for people who act like founders - driven by the mission, biased toward action, and committed to craft.

Lemma
Founded:2025
Batch:F25
Team Size:2
Status:
Active
Location:San Francisco
Founders
Cole Gawin
Cole Gawin
CTO
Jerry Zhang
Jerry Zhang
CEO