CLISP

CLISP is an implementation of the programming languageCommon Lisp originally developed by Bruno Haible and Michael Stoll for the Atari ST. Today it supports the Unix and Microsoft Windowsoperating systems.

CLISP includes an interpreter, a bytecodecompiler, debugger, socket interface, high-level foreign language interface, strong internationalization support, and two object systems: Common Lisp Object System (CLOS) and metaobject protocol (MOP).

It is written in C and Common Lisp. It is now part of the GNU Project and is free software, available under the terms of the GNU General Public License (GPL).