https://www.ycombinator.com/companies/foundry/jobs/uwi8b6I-founding-engineer-ml-x-swe

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[58c5d9a291]

Foundry

World Model for Browser Agents

Founding Engineer (ML x SWE)

$120K - $180K / 3.00%
Location
San Francisco, CA, US / Remote (US)
Job Type
Full-time
Experience
3+ years
Connect directly with founders of the best YC-funded startups.
Apply to role >
Manil Lakabi
Manil Lakabi
Founder

About the role

Stop building GPT wrappers. Build a world model instead.

---------------------------------------------------------------------

Why Foundry exists:

Every SaaS app, enterprise tool, and internal workflow without an API
will soon be automated by browser agents--not traditional API
integrations. Tens of trillions of dollars in global labor depend on
browser-based workflows that no AI system can reliably automate
today.

But browser agents right now are like GPT-1: impressive demos, but
brittle and broken in practice. To scale browser agents from GPT-1
demos to GPT-4 reliability--and unlock this enormous economic
leap--they need purpose-built infrastructure:

  * Hyper-realistic, deterministic web simulations
  * Comprehensive annotation framework for labeling and debugging
  * Reliable benchmarks immune to web drift, IP bans, and rate limits
  * Robust RL training environments and infrastructure

No one's built it yet. We're going first.

We're building exactly this--core infrastructure designed from first
principles, specifically for browser agents. No incremental tools, no
wrappers around GPT--just the foundational AI stack everyone else will
depend on later.

Our founding team is ex-Scale AI & Meta

---------------------------------------------------------------------

What we're looking for:

A founding engineer who's cracked at software engineering--but who now
wants to ship core ML systems and RL infrastructure from scratch.

This is not another prompt-engineering job.

You'll:

  * Build a browser agent gym--sparse rewards, non-determinism, messy
    DOM trees.
  * Solve hard ML problems at the edge of production--every single
    day.

---------------------------------------------------------------------

You probably:

  * Are a killer engineer (Python, TypeScript)
  * Ship insanely fast--internships, side projects, OSS, real
    research--things you've built yourself.
  * Have real ML exposure: trained models, built infra, ran
    experiments.
  * Have strong OSS contributions, publications we'd recognize, or
    both.
  * Want a grind. Want to get better. Want to build something
    genuinely novel.

---------------------------------------------------------------------

Bonus points:

  * You've built RL agents, browser automation (Puppeteer,
    Playwright), or eval tooling.
  * You're tired of wrapping APIs and fine-tuning HuggingFace
    models--ready to do something deeper.

---------------------------------------------------------------------

Why join:

  * Real-world ML infrastructure, real users, real technical
    complexity.
  * Early equity, competitive pay, and massive growth trajectory.

We're building core infra. The ML stack everyone else will use
later--that's what we're shipping today.

---------------------------------------------------------------------

If you've read this far, you probably get it.

Reach out directly--let's build.

About Foundry

We're building the first end-to-end evaluation and training platform
for web agents. Our system enables teams to test, benchmark, and
optimize browser automation models at scale.

  * Deterministic Web Simulation - Stable, reproducible testing with
    versioned web snapshots.
  * Live Web Evaluation - Identify failures caused by UI drift,
    captchas, and dynamic content.
  * Automated Annotation & Labeling - Generate high-quality training
    data for benchmarking.
  * RL-Driven Agent Optimization - Improve models with scalable,
    feedback-driven learning.

By combining synthetic user simulations, automated evaluations, and
large-scale benchmarking, we help teams build more reliable web
agents that handle real-world environments with confidence.

Foundry
Foundry
Founded:2024
Batch:F24
Team Size:2
Status:
Active
Location:San Francisco
  
 
X (Twitter) logo
Founders
Manil Lakabi
Manil Lakabi
Founder
 
 
Pranav Raja
Pranav Raja
Founder
 
 

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