Cajal YC Application

Winter 2026Active

Cajal went through Y Combinator in the Winter 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: Winter 2026
Industry: B2B
Team size: 2
Status: Active
Launched: 2026

Founders

Pedro NobreFounder
Luke JohnstonFounder

What Cajal does

Cajal (YC W26) is massively scaling formal verification to accelerate scientific discovery. We deploy superhuman AI mathematicians to high-impact applied domains, starting with quantum computing and finance. We do this with Lean - a framework that allows us to formally verify any mathematical statement, grounding AI in truth and validating the tools discovered by our systems.

Cajal's YC application, reconstructed

Y Combinator application

Cajal, Winter 2026 batch. The real form questions, answered from public data.

Founders2
Company7
Progress7
Idea4
Equity3
Curious2
Batch Preference1

Company

Company name

Cajal

Describe what your company does in 50 characters or less.

Scaling formal verification to accelerate science

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

We build a platform using Lean to formally verify mathematical statements in applied fields like quantum computing and finance. Our AI mathematicians generate and check proofs, grounding AI discoveries in mathematical truth so users can trust and build upon them.

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

We live in San Francisco, and the company is based here and will remain here after YC.

Explain your decision regarding location.

San Francisco has the right mix of technical talent and investors interested in deep tech and AI enabling scientific discovery. Being here helps us recruit and meet domain experts.

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 Cajal YC application?

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