Better Scheme
Language designed and largely implemented, now a matter of coding, documenting. Goals: high consistency; improve language's functional nature; consistency with lambda calculus; optimize, but not at cost of other goals.
url: www.cs.oberlin.edu/~jwalker/bscheme/
Bigloo
System with one goal: enable Scheme-based programming style where C(++) is usually needed; makes Scheme practical via features found in most traditional languages but not Scheme and functional programming. [Open Source, GPL]
url: www-sop.inria.fr/mimosa/fp/Bigloo/
Chez Scheme
A Scheme implementation. [Commercial]
url: www.scheme.com/csv6.html
CHICKEN
A Scheme compiler which compiles a subset of R5RS into C. Uses the ideas presented in Baker's paper "Cheney on the MTA". It is small and easily extendable, although not a production quality or high-performance Scheme system.
url: www.call-with-current-continuation.org/chicken.htm...
CMU AI Repository Free/Shareware Scheme Implementations
Yet more Scheme implementations from the CMU AI Repository. Many of these are also available from the Indiana University Scheme Repository.
url: www-2.cs.cmu.edu/afs/cs/project/ai-repository/ai/l...
DrScheme
Full Scheme programming environment for Macintosh, many Unixes, Windows. Has module and object systems, platform-independent graphics. Ideal for beginners; one of the major design goals is a flexible teaching environment.
url: www.drscheme.org/
3DScheme
Two systems for Windows with built in "industrial-strength" solid modeler based on the ACIS solid modeler Geometric Modeling Kernel.
url: www.schemers.com/3dscm1.html
EdScheme
Interpreter for Macintosh or Windows. Has "friendly and convenient interactive programming environment" with language sensitive editor, full documentation. [commercial, free 14 day download]
url: www.schemers.com/edschem.html
Elk (Extension Language kit)
(old site, last update in 1997) An embeddable, reusable extension language subsystem for applications written in C or C++. Elk is also a useful standalone Scheme implementation with interfaces to POSIX, Unix, and X11.
url: www-rn.informatik.uni-bremen.de/software/elk/
Elk Scheme - the Extension Language Kit
(new site) An embeddable, reusable extension language subsystem for applications written in C or C++. Elk is also a useful standalone Scheme implementation with interfaces to POSIX, Unix, and X11.
url: sam.zoy.org/projects/elk/
Galapagos
An interactive multithreaded Scheme interpreter with turtle graphics for Windows 95, based on SCM.
url: www.cs.bgu.ac.il/~elad/GALAPAGOS/
Gambit
Scheme system for DOS, Macintosh, Unix, Windows 32-bit, by Marc Feeley. Developed at University of Montreal. [Free to academic research, education]
url: www.iro.umontreal.ca/~gambit/
Hotdog
A nearly R5RS compliant Scheme compiler with multiple backends, currently including .NET, JVM, and C. [Public Domain]
url: rover.cs.nwu.edu/~scheme/
Indiana University Scheme Repository: Implementations
Even more Scheme implementations freely available from the Indiana U. repository.
url: www.cs.indiana.edu/scheme-repository/imp.html
Infer Project
Statically-typed Scheme dialect, written in Infer, combines many of the best features of Scheme and ML. NSF funded.
url: www.cs.indiana.edu/~chaynes/infer.html
Inlab Scheme
A commercial Scheme which is freely available for non-commercial use on Linux and FreeBSD. It has support for several features like bitmap/greymap processing and can be used as a general tool for image processing, OCR or specialized optical object and pattern recognition.
url: www.inlab.de/scheme/
Kali Scheme
A distributed implementation of Scheme that permits efficient transmission of higher-order objects such as closures and continuations.
url: www.neci.nj.nec.com/PLS/Kali.html
The Ksi Scheme Interpreter
Ksi is a portable, embeddable Scheme implementation written in C. Unfortunately its documentation is all in Russian at this point.
url: ksi.sourceforge.net/
KSM-Scheme
A R5RS Scheme interpreter which integrates with C, allowing calling of C functions and accessing C variables from Scheme. It provides a mechanism to load C shared libraries. It runs on x86 and PowerPC based Linux systems.
url: square.umin.ac.jp/~hchang/ksm/
Larceny
A simple and efficient run-time system for Scheme, currently running on the SPARC architecture. A portable implementation that generates C (dubbed "Petit Larceny") is also being developed.
url: www.ccs.neu.edu/home/will/Larceny/index.html
LispMe
Fred Bayers home page is really the home of this Scheme for 3COM Pilot PDA systems: compiler and runtime system intended mainly as a tool to quickly try ideas and algorithms, but can write dialog-based applications.
url: www.geocities.com/SiliconValley/Lab/9981/main.html
LispMe
Newer versions here. Scheme system for the Palm Pilot PDA developed by Fred Bayer.
url: www.lispme.de/lispme/index.html
MIT Scheme
From MIT, for many systems, has comprehensive code library, includes most functionality of ANSI Standard Common Lisp (CLtL2), many low-level OS interactions. Distributed with system is LIAR (LIAR Imitates Apply Recursively), optimizing compiler that outputs native machine code, has Edwin interactive Emacs-derived editor written in pure Scheme and the subject of an MIT AI Lab Memo. Arguably one of the best Scheme systems available, unarguably one of largest. Major downfall: its not totally R5RS compliant, more so for hygienic macros and #f versus the empty list. Version 7.5 now available for x86 systems.
url: www.swiss.ai.mit.edu/projects/scheme/
MzScheme
Small, embeddable, scripting PLT Scheme implementation: R5RS compliant, full numerical tower, threads (all platforms), exceptions, modules, class-based objects, regular-expression matching, TCP/IP. For Macintosh, Unix, Windows 32-bit.
url: www.plt-scheme.org/software/mzscheme/
narsi
A portable scheme interpreter by Britt Park. Also other free software, including: Cdoc - a simple program to generate pretty TeX output from annotated c or c++ code; Userblock - a simple user space block device driver kit for Linux; UVFS - a user space filesystem kit.
url: www.sciencething.org/geekthings/
Open Scheme
From Erian Concept, has CLOS-like object system; runs on Be/x86, FreeBSD, Linux/x86, Solaris (SPARC, x86), Windows. [commercial, unlimited free download evaluation copy with registration]
url: www.open-scheme.com/
Petite Chez Scheme
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. [Freeware]
url: www.scheme.com/petitecs.html
PLT Scheme
Advocacy and authoring group, umbrella name for family of implementations: DrScheme (Scheme, MzScheme, MrEd); books: How to Design Programs, How to Use Scheme; and TeachScheme! project. University-based, supported by many volunteers writing code, documentation.
url: www.plt-scheme.org/
Pocket Scheme
For MIPS, SH3, ARM-based Windows CE devices. Supports Aubrey Jaffer's SLIB, has initialization file for same, parenthesis-balancing text editor. Windows NT version exists. [Open Source, Artistic License]
url: www.mazama.net/scheme/pscheme.htm
Pseudoscheme
Embeds Scheme in Common Lisp.
url: www-swiss.ai.mit.edu/ftpdir/pseudo/
QScheme
A fast, small Scheme interpreter which is mostly compliant with the R5RS standard.
url: www.sof.ch/dan/qscheme/index-e.html
RScheme
Portable, extended Scheme with reflective object(-oriented) system, operating system services, modules, threads, many system programming features (integrates with, compiles to C or bytecodes) and useful extensions. [Open Source]
url: www.rscheme.org/
Scheme 48
A small and portable implementation based on a bytecode interpreter designed to be used as a testbed for experiments in implementation techniques.
url: s48.org/
Scheme 48 manual pages
HTMLified by Margaret Fleck, one of the authors of Envision.
url: www.cs.hmc.edu/~fleck/envision/scheme48/user-guide...
Scheme->C
DEC's venerable Scheme to C translator which runs on most anything with an ANSI C compiler.
url: ftp.cs.indiana.edu/pub/scheme-repository/imp/Schem...
SCM
A portable Scheme implementation written by Aubrey Jaffer.
url: www-swiss.ai.mit.edu/~jaffer/SCM.html
Scsh
A broad-spectrum systems-programming environment for Unix embedded in R5RS Scheme (actually within version 0.53 of Scheme48). Support for concurrent system programming, sophisticated I/O and automatic garbage collection for process resources.
url: www.scsh.net/
Scsh FAQ
The FAQ for Scsh, the Scheme Shell.
url: www-internal.alphanet.ch/~schinz/scsh-faq/scsh-faq...
SIOD: Scheme in One Defun/Day
Very small, portable implementation, has some database, Unix programming, CGI scripting extensions. Runs on DOS, Linux, Unix, Windows. Free source downloads.
url: people.delphiforums.com/gjc/siod.html
Sizzle
A Scheme interpreter implemented as a library which can be embedded into C programs, as well as a standalone interpreter. Mostly R5RS, Guile compatible, and includes regular expressions and most Posix functions.
url: uebb.cs.tu-berlin.de/~magr/sizzle/sizzle.en.html
Stalin
A powerful optimizing Scheme compiler from Jeffery Mark Siskind at the NEC Research Institute. Sacrifices functions such as call/cc in favor of efficiency, but generated code is remarkably bulletproof and fast.
url: www.ece.purdue.edu/~qobi/software.html
STk
A free R4RS Scheme interpreter which can access the Tk graphical package.
url: kaolin.unice.fr/STk/
STklos
Derived from STkn implementation based on an ad-hoc virtual machine, byte compiler; compilable as library to embed in other programs, has object system with MOP, multiple inheritance, generic functions, multimethods, module system, full R5RS tower of numbers, link to GTK+ X toolkit; almost R5RS compliant (in process), to support as many final SRFIs as possible, now supports SRFI-6.
url: kaolin.unice.fr/STklos/
SXM, CXEMA
Portable Scheme implementation, conforms to IEEE/ANSI standard, supports all features of R5RS Report, many features of Chez Scheme and various SRFIs. Derived from XScheme: object system dropped, many changes, additions.
url: www.malgil.com/sxm/
TinyScheme
A tiny implementation of Scheme based on MiniSCHEME. It provides almost complete coverage of R5RS Scheme. Geared towards embedded scripting use, but also functions as a standalone interpreter and extensible shell tool. Recent changes have gotten the executable size down to approximately 64KB on Linux/x86.
url: tinyscheme.sourceforge.net/
VSCM
A portable Scheme implementation written by Matthias Blume of Princeton University. No longer actively developed.
url: www.cs.princeton.edu/~blume/vscm/
Vx-scheme
A compact (<64 Kb) implementation of R4RS Scheme that compiles for VxWorks/Tornado (and is integrated with the system symbol table). [Open source, Artistic License]
url: colin-smith.net/vx-scheme/
WinScm
Scheme environment for Windows 3.1/95; interpreter independent, though defaults to Jaffer's SCM. Used at University of Lille 1, France, for introductory programming course. Free downloads. English, Française.
url: www.lifl.fr/~routier/enseignement/winscm/winscmeng...
XLISP
A superset of the Scheme dialect of Lisp with extensions to support object-oriented programming.
url: www.mv.com/ipusers/xlisper/
