Chez Scheme

Chez Schemetm is a complete high-performance implementation of ANSI/IEEE standard Scheme, with a fast incremental compiler, an efficient run-time system, an extensive run-time library, and a productivity-enhancing program development environment. Chez Scheme was first introduced in 1985 and is now in its sixth major release. Chez Scheme is distributed by Cadence Research Systems.

More information on Chez Scheme is available at

Free Software and Documentation Related to Chez Scheme

Petite Chez Scheme

Petite Chez Scheme is a complete Scheme system that is fully compatible with Chez Scheme but uses high-speed threaded interpreter technology in place of Chez Scheme's incremental native-code compiler. Programs written for Chez Scheme run unchanged in Petite Chez Scheme, as long as they do not depend specifically on the compiler. In fact, Petite Chez Scheme is built from the same sources as Chez Scheme, with all but the compiler sources included.

Petite Chez Scheme may be used without license fee or royalty for any purpose, including for resale as part of a commercial product. (See the license agreement shipped with Petite Chez Scheme for details.)

The white paper Distributing Applications with Petite Chez Scheme describes Petite Chez Scheme and its use as a distribution vehicle. An updated version of the white paper has been incorporated into Chapter 2 of the Chez Scheme Version 8 User's Guide.

The latest version of Petite Chez Scheme is available at

Scheme Widget Library (SWL)

The Scheme Widget Library (SWL) is a free windowing and graphics package for Chez Scheme developed in the Indiana University Computer Science Department with support from the National Science Foundataion and Cadence Research Systems. It includes an object system for Scheme, a threaded windowing and graphics library, and various tools, including a window-based REPL (read-eval-print loop) window, a simple editor, a source-file viewer, and a document viewer.

SWL runs both on Unix-based platforms and under Windows with either Chez Scheme or Petite Chez Scheme. It can be built from sources only by Chez Scheme, since building it requires the compiler. It is available in source-code form and in binary form for various supported platforms at

SWL is based on Scriptics' Tcl/Tk system.

On-line Documentation

Two complete on-line books relating to Chez Scheme are available.

Other related items include:

A more extensive list of documents relating to Chez Scheme and its implementation is avaiable in a separate list:

Portable Syntax-Case

The portable syntax-case macro system is described on the portable syntax-case page.


A pattern matcher developed for use in our Indiana University's compiler course is available in the file, and a brief document describing its use is also available.