Common Lisp implementations

SBCL

Steel Bank Common Lisp is a high performance Common Lisp compiler. It is open source, with a permissive license. Besides the compiler and runtime system for ANSI Common Lisp, it provides an interactive environment with a debugger, a statistical profiler, a code coverage tool and many other extensions. SBCL runs on a number of POSIX platforms, and on Windows.

ASDF: yes · Quicklisp: yes

docker run --rm -it clfoundation/sbcl

Clozure CL

Clozure CL (CCL for short) is a free Common Lisp implementation with a long history. It is known for its fast compilation, native threads, a precise, generational, compacting garbage collector and a convenient foreign-function interface. It is distributed under the Apache License, version 2.0.

ASDF: yes · Quicklisp: yes

docker run --rm -it clfoundation/ccl

ECL

Embeddable Common Lisp implements the language with an interpreter and a translator to C that can produce standalone executables and libraries to embed in other programs. It runs on Linux, the BSDs, macOS, Solaris and Windows, on Intel, ARM and other processors.

ASDF: yes · Quicklisp: yes

docker run --rm -it clfoundation/ecl

ABCL

Armed Bear Common Lisp is a full implementation of the language with both an interpreter and a compiler, running on the JVM. It supports JSR-223, so it can be the scripting engine of any Java application, and its Java integration lets parts of an application be written in Lisp.

ASDF: yes · Quicklisp: yes

docker run --rm -it clfoundation/abcl

Clasp

Clasp interoperates seamlessly with C++ libraries and programs, using LLVM to compile to native code. It opens a vast array of existing libraries, such as those of scientific computing, to Lisp's rapid prototyping and incremental development.

ASDF: yes · Quicklisp: yes

docker run --rm -it clfoundation/clasp

CLISP

CLISP is a Common Lisp implementation by Bruno Haible and Michael Stoll. It implements the language described in the ANSI standard, with many extensions.

ASDF: yes · Quicklisp: yes

docker run --rm -it clfoundation/clisp

CMUCL

CMU Common Lisp is a free, high-performance implementation that runs on most major Unix platforms. Its compiler, Python, is the ancestor of SBCL's.

ASDF: yes · Quicklisp: yes

docker run --rm -it clfoundation/cmucl

GCL

GNU Common Lisp compiles Lisp to C and hands it to the system's C compiler for native code. It is the GNU project's Common Lisp, and a long-standing host of the Maxima computer algebra system and the ACL2 theorem prover.

ASDF: from 2.7.1 · Quicklisp: no

Allegro CL

Allegro CL® is a powerful dynamic object-oriented development system, especially suited to enterprise-wide, complex application development, with applications of billions of objects in fields from the life sciences to manufacturing to financial analytics.

ASDF: yes · Quicklisp: yes

LispWorks

LispWorks® is an implementation of ANSI Common Lisp for Windows, Linux, macOS and other platforms, source-compatible across all of them. It offers an advanced compiler, the CAPI portable GUI toolkit and the LispWorks IDE.

ASDF: yes · Quicklisp: yes

Evergreen

Evergreen Common Lisp (EGCL) is an experimental implementation written in Rust, with a tiered JIT that moves hot code from bytecode to native compilers, a moving generational garbage collector, fibers, and a tree shaker for standalone executables. It runs on Linux, macOS, Windows and Android. Its author promises neither full ANSI conformance nor production readiness, and says its code was written almost entirely by AI assistants.

ASDF: yes · Quicklisp: with patches

docker run --rm -it clfoundation/egcl

dotcl

dotcl, by Masatoshi Sano, is Common Lisp on .NET: Lisp compiles to CIL and runs on the .NET JIT, and Lisp values are .NET objects, so it embeds in C# and Unity programs with no marshalling layer, or runs on its own with a REPL and Quicklisp. It is new in 2026.

ASDF: yes · Quicklisp: yes

docker run --rm -it clfoundation/dotcl

AmiLisp

AmiLisp, first released as CL-Amiga, is Manfred Bergmann's bytecode-compiled Common Lisp in C for classic Amiga hardware, AmigaOS 3 on a 68020 and MorphOS, with CLOS and the MOP, threads, sockets and Quicklisp. It also builds on macOS, Linux and Windows. It is alpha software, and its ANSI conformance is incomplete.

ASDF: yes · Quicklisp: with patches

SICL

SICL is a fresh implementation of Common Lisp, led by Robert Strandh, built as modules other implementations can adopt: Clasp already uses its reader, Eclector, and its compiler framework, Cleavir. SICL itself is developed by bootstrapping inside SBCL and has no standalone release yet.

ASDF: no · Quicklisp: no

MKCL

ManKai Common Lisp, by Jean-Claude Beaudoin, grew out of ECL's source and carries on the Kyoto Common Lisp line, aiming at full ANSI conformance with an emphasis on reliability. It compiles through C, is multithreaded only, and runs on Linux and Windows. Its last release, 1.1.11, came out in 2019; development toward 1.2.0, with a complete C99 FFI and image dump and load, continues on its master branch.

ASDF: yes · Quicklisp: yes

Genera

Genera, the operating system and development environment of the Symbolics Lisp Machines, runs today on the Virtual Lisp Machine, an emulator of the Ivory processor that boots the original world image unmodified, on macOS on Apple Silicon and on Linux on ARM and x86. Symbolics Technologies licenses it by invitation, through its Friends of Symbolics program, ahead of broader availability.

ASDF: yes · Quicklisp: no

Medley

Medley, the Interlisp environment from Xerox PARC, includes Xerox's Common Lisp beside Interlisp, the two calling each other freely. Its Common Lisp sits between the first and second editions of Common Lisp the Language, and the Medley Interlisp Project, which revived the system under the MIT license, has ANSI conformance as a goal. Its emulator, Maiko, runs it on Linux, macOS and Windows, and it runs in a web browser too.

ASDF: no · Quicklisp: no

uLisp

uLisp, by David Johnson-Davies, is a subset of Common Lisp for microcontrollers, from AVR chips with 2 kB of RAM up to ARM, ESP32 and RISC-V boards, with an interpreter on the board and a REPL over its serial line. It is still developed, and has grown a compiler to RISC-V machine code written in uLisp itself.

ASDF: no · Quicklisp: no

Mezzano

Mezzano is an operating system written in Common Lisp, with its own implementation of the language at its core. Its demo releases run on x86-64 in VirtualBox or QEMU, and on some real hardware.

ASDF: yes · Quicklisp: yes

JSCL

JSCL compiles Common Lisp to JavaScript and runs in the browser, Node.js and Deno. It is a subset of Common Lisp by design, with CLOS, LOOP, FORMAT and packages, and calls itself far from complete.

ASDF: no · Quicklisp: no

Valtan

Valtan is a Common Lisp to JavaScript compiler that aims at ANSI compatibility, with macros, source maps and JavaScript interop. It calls itself alpha, and tests against the SACLA suite until ansi-test is within reach.

ASDF: no · Quicklisp: no

KCL

Kyoto Common Lisp, by Taiichi Yuasa and Masami Hagiya, was one of the first implementations of the language, written in C from the 1984 Common Lisp the Language alone. Its last release was in 1987. It lives on in its descendants: AKCL and then GCL, and ECL, from which MKCL grew.

Ibuki CL

Ibuki Common Lisp was the commercial KCL: Richard Weyhrauch founded Ibuki in 1985 to sell an improved KCL in the United States, and by the mid-1990s it ran on more than 30 platforms.

Golden CL

Gold Hill's Golden Common Lisp, from Cambridge, Massachusetts, brought Common Lisp to MS-DOS PCs in 1984. Early versions were far from the full language; release 3, in 1988, came close to it. Gold Hill also sold GoldWorks, an expert-system tool for MS-DOS.

TI Explorer

Texas Instruments' Explorer was a Lisp Machine of the 1980s, from the MIT Lisp Machine line by way of LMI. Its system, written in Zetalisp, supported Common Lisp as well. The Meroko emulator boots an Explorer I's software to Lisp.

VAX LISP

Digital Equipment's VAX LISP, for VMS and ULTRIX, was the first Common Lisp written for machines other than Lisp Machines, bootstrapped from Carnegie Mellon's Spice Lisp. Version 2.0 shipped in 1986.

Butterfly Lisp

BBN's Butterfly Lisp ran Common Lisp and Scheme on the Butterfly, a shared-memory multiprocessor of up to 256 nodes, with parallelism through futures and a parallel garbage collector. It grew from MIT's MultiScheme, around 1987.

AKCL

Austin Kyoto Common Lisp was William Schelter's work on KCL at the University of Texas at Austin from the late 1980s: ports to many Unix workstations, fixes and speedups. In 1994 it became GNU Common Lisp.

Lucid CL

Lucid Common Lisp was a leading commercial implementation for Unix workstations in the late 1980s. After Lucid failed in 1994 it passed to Harlequin and then to LispWorks Ltd, which lists it as Liquid Common Lisp and offers to move old applications built on it to modern platforms.

MCL

Macintosh Common Lisp, from Coral Software and then Apple and Digitool, was the Common Lisp of the classic Mac OS and of PowerPC Mac OS X. Version 5.2 was opened as source, and RMCL, released in 2009, ran it on early Intel Macs through Rosetta. Clozure CL began in 1998 as a port of its compiler and runtime.

ExperCommon Lisp

ExperCommon Lisp, from ExperTelligence of Santa Barbara, was an early Common Lisp for the Macintosh. By 1989 ExperTelligence was selling Procyon's Common Lisp for the Mac instead, free to ExperCommon Lisp owners who bought its CLOS.

Procyon CL

Procyon Common Lisp, from Procyon Research of Cambridge, England, had the first commercial CLOS, on DOS, OS/2, the Macintosh and Windows. Franz bought the Windows version in 1992 and developed it into Allegro CL for Windows.

CLOE

CLOE was Symbolics' Common Lisp for 386 PCs under MS-DOS, from 1988: applications were developed on a Symbolics machine and delivered on the PC, with CLOS, the condition system and a generational garbage collector.

Poplog

Poplog, from the University of Sussex, compiles POP-11, Common Lisp, Prolog and Standard ML incrementally into one environment, so one program can mix them. Commercial until 1999 and open source since, its last release, 16, came in 2020; the GetPoplog project keeps it installable on Linux.

SubL

SubL is the variant of Common Lisp that Cyc, the knowledge base and inference engine, is written in. Cycorp made it to carry Cyc off Lisp Machines: SubL runs on Allegro CL and is translated to Java, and earlier was translated to C. It lives inside Cyc and is not offered on its own.

Top Level CL

Top Level Common Lisp grew from Parallel Common Lisp at the University of Massachusetts and was sold by Top Level Inc. from 1990, for the Sequent Symmetry and Encore Multimax multiprocessors. Built on CMU Common Lisp, it offered futures at four grain sizes.

XLISP

David Betz's XLISP, first released in 1983, was a small Lisp in C that moved toward Common Lisp from version 2.0 without becoming one. Its forks went further: Tom Almy's XLISP-PLUS added more of Common Lisp, and Luke Tierney's XLISP-STAT made it a statistics environment.

Star Sapphire

Star Sapphire Common LISP, from Sapiens Software, was an inexpensive subset of Common Lisp for MS-DOS and Windows PCs in the early 1990s, with an Emacs-like editor, a compiler, a debugger, CLOS and DOS graphics.

WCL

Wade Hennessey's WCL provides Common Lisp as a Unix shared library, linked with Lisp and C code into small executables, so that many Lisp programs can be installed and run at once; Hello World comes to 20 kB on 32-bit x86 Linux. It was presented at the 1992 Lisp and Functional Programming conference. Its source is on GitHub, unchanged since 2017.

CLiCC

CLiCC, from the University of Kiel, compiled a subset of Common Lisp without EVAL into C programs, for delivering applications rather than developing them. Its last release, 0.6.4, came out in 1994.

Codemist CL

Codemist Common Lisp, from Arthur Norman and John Fitch's Codemist, was the Lisp under the commercial Axiom computer algebra system while NAG sold it. Built for delivery from Codemist Standard Lisp, the Lisp of REDUCE, it had its source released in 2002.

L

L, by Rodney Brooks and Charles Rosenberg at IS Robotics, the company that became iRobot, was a small Common Lisp for the processors inside the company's autonomous robots: 16 MHz 68020s with a megabyte of memory. It was presented in 1995.

Eclipse

Eclipse Common Lisp, written by Howard Stearns at Elwood Corporation and released in 1997, is an ANSI implementation in C and Lisp that compiles Lisp to C and links it into its runtime. Its source has been open since 2015, and Blake McBride keeps it building on Linux.

Corman Lisp

Roger Corman's Common Lisp for Windows compiles to native code and works closely with the Windows API. He opened its source under the MIT license in 2015. The community's release 3.1, in 2018, brought it to 64-bit Windows as a 32-bit program, and it has not changed since 2019.

Movitz

Movitz, by Frode Vatvedt Fjeld, runs Common Lisp on bare x86 PCs with no operating system, as a platform for kernels and embedded programs. It never reached the full standard, and development has stopped; its project page is here on common-lisp.net.

ThinLisp

ThinLisp, by Jim Allard and Ben Hyde, translates a restricted Common Lisp into C for delivering commercial applications, running inside another Common Lisp as the translator; the programs it makes have no garbage collector. Its last version, with Vladimir Sedach's patches, is hosted here on common-lisp.net.

Scieneer CL

Douglas Crosher's Scieneer Common Lisp, a commercial descendant of CMUCL, was built for multithreading on multiprocessor machines and for 64-bit platforms, on Linux, Solaris and HP-UX. Its site has not changed since 2015 and its product pages are gone; the link is to an archived copy.

XCL

XCL, by Peter Graves, the original author of ABCL, has a kernel in C++ and an optimizing compiler for x86 and x86-64, on Linux, FreeBSD and 32-bit Windows. Its repository has not changed since 2017.

Ufasoft CL

Ufasoft Common Lisp is a fork of GNU CLISP for Windows that keeps most of CLISP's Lisp files but reimplements its C core in C++, with an IDE and EXE output, under the GPL. Its last version is 4.37, and its site has not changed since 2013.

mocl

mocl, from Wukix, compiled Common Lisp for iOS, Android and macOS applications, and came with a REPL that ran on the device. It was first released in 2013, its last release came in 2014, and its site no longer answers.

npt

npt is an ANSI Common Lisp in C, for FreeBSD, Linux and Windows, released into the public domain under the Unlicense. Its repository has not changed since 2023.