https://www.ycombinator.com/companies/keystone/jobs/J3t9XeM-founding-engineer

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[8c3915c83d]

Keystone

Your team's on-call AI engineer

Founding Engineer

$150K - $300K*0.50% - 3.00%*San Francisco, CA, US
Job type
Full-time
Role
Engineering, Full stack
Experience
1+ years
Visa
US citizen/visa only
Skills
Python, React, TypeScript
Connect directly with founders of the best YC-funded startups.
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Pablo Hansen
Pablo Hansen
Founder
Pablo Hansen
Pablo Hansen
Founder

About the role

About Keystone

We're building AI-native error monitoring that automatically
investigates production issues and generates code fixes. Think
Sentry, but built from the ground up for a world where AI can
actually understand your codebase, trace through logs, and tell you
exactly what broke and how to fix it.

We're starting here and expanding until we're the default tool for
building product, period. Our mission is to free engineers from the
drudgery of digging through logs, setting up systems, and debugging-
so they can focus on understanding users and designing great
products.

We're in-person in SoMa, San Francisco. We raised a $5.2M seed from
True Ventures, Twenty Two Ventures, Pear VC, and Ritual Capital- plus
the founders of YC, Dropbox, Supabase, Eight Sleep, Graphite, Resend,
RocketMoney, and more. Early design partners include teams at
Perplexity and Lovable.

About the Role

You'd be the first engineering hire, working directly with me (the
founder) to build the core product. You'll have more ownership and
influence over the product, culture, and technical direction than
you'd get almost anywhere else.

Example projects:

  * 2-week sprint to build a new product vertical from scratch
  * Design a new interface for engineering workflows that wasn't
    possible until a model advancement that came out yesterday

You might be a great fit if you:

  * Have shipped products end-to-end (frontend to infra) and obsess
    over the details
  * Work fast and comfortably with ambiguity- we're figuring things
    out as we go
  * Get excited about hard problems at the intersection of AI and
    developer tools
  * Want to be genuinely early, not "early at a 50-person series B"

Stack: TypeScript, React (Next.js), Python, Postgres, Redis, AWS

Comp & benefits: Top-of-market salary + significant equity, full
health/dental/vision, all meals covered, equipment budget

About the interview

If there appears to be a fit, we'll reach to schedule 2-3 short
technicals. After, we'll schedule an onsite in our office, where
you'll work on a small project, discuss ideas, and get a sense for
our in-person culture.

About Keystone

Keystone
Keystone
Founded:2025
Batch:S25
Team Size:1
Status:
Active
Location:San Francisco
  
 
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Founders
Pablo Hansen
Pablo Hansen
Twitter account 
 
Founder
Pablo Hansen
Pablo Hansen
Twitter account 
 
Founder

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