Allegro CL Alternatives

Racket is a general-purpose programming language as well as the world’s first ecosystem for language-oriented programming.

Hy is a wonderful dialect of Lisp that’s embedded in Python.

Since Hy transforms its Lisp code into the Python Abstract Syntax Tree, you have the whole beautiful world of Python at your fingertips, in Lisp form!.

Guile is the GNU Ubiquitous Intelligent Language for Extensions, the official extension language for the GNU operating system. It's an implementation of the Scheme programming language, supporting the Revised5 and most of the Revised6 language reports, as well as many SRFIs.

Implementation of Scheme providing an interpreter, compiler, source-code debugger, integrated Emacs-like editor, and a large run-time library.

Steel Bank Common Lisp (SBCL) is a high performance Common Lisp compiler. It is open source / free software, with a permissive license. In addition to the compiler and runtime system for ANSI Common Lisp, it provides an interactive environment including a debugger, a statistical...

Armed Bear Common Lisp (ABCL) is a full implementation of the Common Lisp language featuring both an interpreter and a compiler, running in the JVM. Originally started to be a scripting language for the J editor, it now supports JSR-223 (Java scripting API): it can be a...

CLISP is a portable ANSI Common Lisp implementation and development environment by Bruno Haible. Interpreter, compiler, debugger, CLOS, MOP, FFI, Unicode, sockets, CLX. UI in English, German, French, Spanish, Dutch, Russian, and Danish.

CMUCL is a free, high performance implementation of the Common Lisp programming language which runs on most major Unix platforms. It mainly conforms to the ANSI Common Lisp standard. CMUCL provides a sophisticated native code compiler; a powerful foreign function interface; an...

ManKai Common Lisp (MKCL) aims to be a full implementation of the Common Lisp language in compliance with the ANSI X3J13 Common Lisp standard. It is free software distributed under the terms of the GNU Lesser General Public License (LGPL) with a few minor exceptions (see the...

Clozure CL (often called CCL for short) is a free Common Lisp implementation with a long history. Some distinguishing features of the implementation include fast compilation speed, native threads, a precise, generational, compacting garbage collector, and a convenient...

GCL is the official Common Lisp for the GNU project. Its design makes use of the system's C compiler to compile to native object code, providing for both good performance and facile portability. GCL currently compiles itself and the primary free software Lisp applications...

LispWorks is a commercial implementation and IDE for the Common Lisp programming language.