CMU Common Lisp

CMUCL
Original authorCarnegie Mellon University
DeveloperVarious
Initial releaseEarly 1980 (1980)
Stable release
21f / October 1, 2025 (2025-10-01)
Operating systemSeveral POSIX-compliant OSs
PlatformCross-platform
Available inCommon Lisp
TypeCompiler and runtime
LicensePublic domain
Websitecmucl.org
Repository

CMUCL is a free Common Lisp implementation, originally developed at Carnegie Mellon University.

CMUCL runs on most Unix-like platforms, including Linux and BSD; there is an experimental Windows port as well. Steel Bank Common Lisp is derived from CMUCL. The Scieneer Common Lisp was a commercial derivative from CMUCL.