OpenProse YC Application

Spring 2026Active

OpenProse went through Y Combinator in the Spring 2026 batch as a B2B company. Below: what the company does, who founded it, and its application to YC, reconstructed question by question in the real YC form.

YC batch: Spring 2026
Industry: B2BEngineering, Product and Design
Team size: 3
Status: Active
Launched: 2026

Founders

Dan BarrettFounder

What OpenProse does

OpenProse is building open-source infrastructure for long-running AI work: a declarative language plus the Reactor harness/runtime for reliable agent workflows. Our organic open-source traction (7k+ installs) has already translated into a customer at a medical research lab, starting with a $10k pilot set to roll into a $10k/month contract. YC recruited us into the current batch and we've since hired two senior founding team members (ex-Google, Forbes 30u30 harness engineer). All three founding team members are two time founders. We just closed a $1m capped SAFE from Jonathan Abrams 8-Bit Capital and expect to raise $2.5-$3m more on Demo Day.

OpenProse's YC application, reconstructed

Y Combinator application

OpenProse, Spring 2026 batch. The real form questions, answered from public data.

Founders2
Company7
Progress7
Idea4
Equity3
Curious2
Batch Preference1

Company

Company name

OpenProse

Describe what your company does in 50 characters or less.

Open-source infrastructure for reliable long-running agents

What is your company going to make? Please describe your product and what it does or will do.

We're building a declarative language and a runtime harness called Reactor that lets teams build and run reliable, long-running AI workflows. Our platform is designed for complex agent tasks that need coordination, error handling, and durability over time.

Where do you live now, and where would the company be based after YC?

We live in San Francisco and remotely; the company is based in San Francisco.

Explain your decision regarding location.

We chose San Francisco because it's where the team is located and where we can easily connect with advanced AI users and early customers, including a medical research lab piloting our product.

21 more answers in the full application

Founders, Progress, Idea, Equity, Curious, Batch Preference are in the full version. Create a free account to open it in YC Insights, next to every other YC batch.

See full application

Frequently Asked Questions

Is this the real OpenProse YC application?

No. Y Combinator keeps submitted applications private. This is a reconstruction: the real YC form questions, answered from OpenProse's public data (launch notes, founder backgrounds, product description). It shows how a company like OpenProse would present itself to YC, not the text they submitted.