The current release of Clozure CL is version 1.9.

The preferred way to get Clozure CL is via Subversion. For example, to get Clozure CL 1.9 for Darwin/x86, you'd type (where the $ is the shell prompt):

$ svn co

To get a version for a different platform, change the darwinx86 to one of linuxx86, freebsdx86, solarisx86, windows, linuxppc, or linuxarm.

All versions include both 32- and 64-bit binaries (except for ARM, which is 32-bit only).

Please see Obtaining, Installing, and Running Clozure CL for details on completing the installation.

After installing CCL, read about getting updates and bug fixes.

If there is some reason you cannot use Subversion, you can download an archive listed in the table below. All these archives are available from or via anonymous ftp from

x86 PowerPC ARM
Mac OS X 10.5 and later .tar.gz
Linux .tar.gz .tar.gz .tar.gz
FreeBSD 6 and later .tar.gz
Solaris .tar.gz
Windows XP and later .zip

Mac users may also elect to install Clozure CL from the Mac App Store.

If you are interested in running the development version of Clozure CL, please see the wiki topic TrackingTheTrunk.

Compatibility Notes

32-bit x86 ports need SSE2

The 32-bit x86 versions of Clozure CL depend on the presence of the SSE2 instructions. Most x86 processors manufactured and sold in the last several years support SSE2 (all Apple Intel-based Macs do, for instance), but there are some exceptions.

The Wikipedia article on SSE2 lists processor models that support SSE2 (and also notes some of the more notable exceptions).

Additional Notes

See also the wiki topics SystemRequirements and PlatformNotes.