Cajal

Cajal is a Y Combinator-backed company that scaling formal verification to accelerate scientific discovery. The company participated in the Winter 2026 batch of Y Combinator.

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 was part of Y Combinator's Winter 2026 cohort, has a team of approximately 2 employees, and is actively operating.