Cajal
Cajal builds tools that prove software correct, down to the compiled program, using the Lean proof checker and AI provers.
Cajal builds tools that prove software correct, down to the compiled program, using the Lean proof checker and AI provers. Its product Tau checks a compiled WebAssembly binary against a written spec and returns a certificate signed by the Lean kernel, or a bug report if the proof fails. Tau runs on Talos, their open-source WebAssembly interpreter written in Lean 4 (https://caj.al/tau, read 2026-10-09). Their Y Combinator profile says they are starting with quantum computing and finance.
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Company details
| Industry | AI & Machine Learning |
| Website | Visit Cajal |
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