Version 50 (modified by rme, 14 years ago) (diff)


Welcome to Clozure CL!

Clozure CL is an open source Common Lisp implementation that runs on PowerPC hardware under Mac OS X and LinuxPPC, and on x86-64 hardware under Linux, Mac OS X, and FreeBSD.

Clozure CL does not yet run on 32-bit Intel processors; a port is underway.

Clozure CL used to be called OpenMCL. It is also sometimes called CCL. You will see the three names being used interchangeably.

Getting Clozure CL

Current snapshots of CCL are available via anonymous ftp at

The most recent snapshot release is from July 2007; there has been a lot of activity since then. Therefore, once you have the snapshot installed and running, you'll probably want to update from sources. See UpdatingFromSource (for CVS users) and UpdateFromSubversion for instructions on how to do that.

Mailing Lists

There are two CCL-related mailing lists hosted at These lists are managed with GNU Mailman software, which provides a simple web-based interface for managing subscription options.

Support and Consulting

Clozure Associates provides commercial support and consulting services for Clozure CL as well as other Common Lisp implementations. These services can range from helping you debug your software to adding extensions to CCL, to providing several full time Lisp programmers to help you build your application. Please contact us at business@… for more information.

Starting Points

CCL Basics

In-Depth CCL

Orient Yourself to Clozure CL Culture

About this site

The contents of this site are managed by Trac, which describes itself as "a minimalistic approach to web-based management of software projects, whose goal is to simplify effective tracking and handling of software issues, enhancements and overall progress." Towards this end, Trac provides a bug tracking system, an interface to Clozure CL's subversion repository, and a unifying Wiki framework.

As it's configured, this Trac instance allows anyone to view Wiki pages, to search for and view "tickets" (bug reports and feature requests), and to browse the OpenMCL source repository. Registered users can add and modify Wiki pages and tickets. (Requiring that users register before modifying content here is intended to discourage spam.)

All Wiki pages are editable. This means that you can (after logging in) modify the contents of any Wiki page simply by using your web browser. Simply click on the "Edit this page" link at the bottom of the page. WikiFormatting will give you a detailed description of available Wiki formatting commands.

TracGuide provides general documentation on the use of Trac's features.

Learn About Trac

For a complete list of local wiki pages, see TitleIndex.