Cajal
Cajal is a YC Winter 2026 (W26) company. Based in San Francisco, CA, USA. Team of 2.
About Cajal
Summary
Cajal builds formal verification infrastructure for AI-generated software, using the Lean proof framework to prove code correct down to the binary level. Its tools replace human code review and testing in environments where machine-written code is produced faster than humans can audit and where AI-driven exploits are a growing threat. The company targets quantum computing and finance as its first applied domains, with broader infrastructure, including an open-source binary lifter called Talos, in active development.
Go-to-market
Cajal targets technical teams in high-stakes industries where software correctness is critical, with open-source tooling like Talos serving as a public entry point alongside direct engagement for applied deployments.
From the Y Combinator listing
Scaling formal verification to accelerate scientific discovery
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.
Facts
- B2B / B2B
- San Francisco, CA, USA
- 2
- Active
- Early
Founders (2)
- Pedro Nobre
Score every batch against your own thesis
GPAgent's sourcing agent reads every company in a batch, scores each one against your fund's thesis in a private workspace, and lines up the founders worth meeting before Demo Day. You decide who to contact. Your scores, notes, and pipeline never appear on these pages.
How Accelerator intelligence works