provers.si
For theorem provers and verified software.
About the name
What provers.si means
A prover is the program that checks, or finds, a mathematical proof. Lean and Isabelle are the familiar names, and AI has pulled them out of the seminar room into a market. Mathlib, Lean's community library, lists more than 290,000 theorems and over 770 contributors on its live statistics page. Harmonic raised a $120 million Series C at a $1.45 billion valuation in November 2025 for Aristotle, a model that answers in Lean proofs. Industry is following: AWS built a formal model of its Cedar authorization language in Lean and proved key safety properties, with 5,714 lines of proof. provers.si is the plural noun for that stack: the checkers, the proof-search models and the libraries engineers build on. Six letters before the dot, and a word every formal-methods hire already uses.
Good fortheorem proversformal verificationproof engineeringverified softwaremath ai labs
Proof search as a service
Verification teams burn weeks closing small lemmas by hand. An API that takes a goal and returns a checked proof, or a precise failure, sells by the closed obligation. A February 2026 paper reported a 7-billion-parameter model proving 51.67% of 660 theorems from seL4's important theories, against 27.06% for earlier work. Buyers: kernel, compiler and chip verification groups.
A registry of proven libraries
Package managers tell you a library compiles. They do not tell you which properties are proven. A registry that indexes proofs next to code, and flags any update that breaks a theorem, gives safety and security teams something to cite in an audit. Revenue comes from private mirrors for companies with certification duties.
Autoformalization for mathematicians
Turning a paper's argument into Lean still takes months of skilled labour. Tooling that drafts the formal statement, finds the matching mathlib lemmas and leaves only the hard steps to a human cuts that time. Sell to university groups, research institutes and the AI labs that want formal mathematics as training data.
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Questions
About provers.si
Who actually uses the word provers?
Engineers, mostly. "Prover" is standard vocabulary in formal methods, automated reasoning and proof engineering, so the name signals depth to the people you hire and sell to. That is the trade: a consumer will not decode it on first read, but a verification lead, a compiler team or a maths AI lab knows what the company does before the homepage loads.
Does provers.si suit chip and kernel verification, or only maths?
Both. Theorem provers already check processor designs, cryptographic code and operating-system kernels. seL4, a general-purpose microkernel with machine-checked proofs running from its C code down to the binary, is the reference case. A company selling proof automation to silicon or embedded teams fits the name as well as a maths lab does.
Why the plural rather than a single prover?
Real verification pipelines chain several engines: SMT solvers for easy goals, interactive provers for hard ones, and now learned models that suggest the next tactic. A plural name describes that orchestration layer honestly. It also leaves room to run many provers, or many AI agents searching for proofs in parallel, under one brand.
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