ACL2

Spec sheet

Purpose

ACL2 combines a Lisp-based programming language for formal models with a reasoning engine that can prove properties about those models.Read 30 Sep 2026 · acl2.org

Integrations

The Community Books include interfacing tools for file I/O, operating-system access, raw Common Lisp libraries, and connections to other programs.Read 29 Sep 2026 · acl2.org

Support

ACL2 users can get help through the acl2-help mailing list, which the site recommends to new users.Read 30 Sep 2026 · acl2.org

Build time

The documentation says building all Community Books can take hours and is usually unnecessary.Read 30 Sep 2026 · acl2.org

Community

The ACL2 community page describes its user community as active and welcoming to new users, with GitHub Issues available for reporting problems.Read 30 Sep 2026 · acl2.org

Community Books

The Community Books include lemma libraries, macros, interfacing tools, proof automation and debugging tools, and specialty libraries such as hardware-verification libraries.Read 30 Sep 2026 · acl2.org

Community libraries

The ACL2 Community Books are open-source libraries that include lemma libraries, macros, interfacing tools, proof-automation and debugging tools, and hardware-verification libraries.Read 29 Sep 2026 · acl2.org

Community support

The acl2, acl2-help, and acl2-books mailing lists serve general discussion, user help, and discussion of developments in ACL2 and its Community Books.Read 29 Sep 2026 · acl2.org

Development snapshot

The page says development snapshots from GitHub are minimally tested and pre-built binary distributions are generally unavailable.Read 30 Sep 2026 · acl2.org

Development version

The installation instructions describe GitHub development snapshots as minimally tested and say prebuilt binaries are generally unavailable for them.Read 29 Sep 2026 · acl2.org

Documentation

Documentation is available online, as downloadable local manuals, through an Emacs browser, and at the ACL2 terminal with the :doc command.Read 29 Sep 2026 · acl2.org

External dependency

Some Community Books based on satlink and gl require an installed SAT solver, typically Glucose.Read 30 Sep 2026 · acl2.org

Installation

Unix-like installation instructions cover Linux, macOS with Intel or ARM processors, and FreeBSD; Windows has separate installation instructions.Read 29 Sep 2026 · acl2.org

Lisp dependency

Installing ACL2 requires a Common Lisp implementation, and some Community Books are guaranteed to work only with CCL or SBCL.Read 30 Sep 2026 · acl2.org

Open source libraries

ACL2 installations include the open-source ACL2 Community Books libraries.Read 30 Sep 2026 · acl2.org

Operating systems

The Unix-like installation instructions cover Linux, macOS, and FreeBSD; separate instructions are available for Windows.Read 30 Sep 2026 · acl2.org

Prerequisite

Installation instructions say users need a Common Lisp implementation, and note that some Community Books depend on Quicklisp and are only guaranteed to work with CCL or SBCL.Read 29 Sep 2026 · acl2.org

Provenance

The manual identifies ACL2 version 8.7 as copyright 2026 Regents of the University of Texas and authored by Matt Kaufmann and J Strother Moore.Read 29 Sep 2026 · acl2.org

Release

The installation page identifies version 8.7 as the latest stable release and says it does not include improvements or fixes made since March 2026.Read 30 Sep 2026 · acl2.org

Use cases

The manual says ACL2 has been used to formally verify systems in academia and industry.Read 29 Sep 2026 · acl2.org

Where Specifiction places it

• Formal Verification Tools#14 of 347.8