CMUCL is a free, high performance implementation of the Common Lisp programming language which runs on most major Unix platforms. It mainly conforms to the ANSI Common Lisp standard. CMUCL provides a sophisticated native code compiler; a powerful foreign function interface; an implementation of CLOS; the Common Lisp Object System; which includes multimethods and a metaobject protocol; a source-level debugger and code profiler; and an Emacs-like editor implemented in Common Lisp. CMUCL is maintained by a team of volunteers collaborating over the Internet, and is mostly in the public domain.
Euphoria is a simple, flexible, easy-to-learn programming language. It lets you quickly and easily develop programs for Windows, Linux, FreeBSD, NetbSD, OpenBSD, and Mac OS X. Although Euphoria provides subscript checking, uninitialized variable checking, and numerous other run-time checks, it is extremely fast and has the ability to compile to transparently compile native executables via C code.
MDK (MIX Development Kit) provides tools for developing and executing, in a MIX virtual machine, MIXAL programs. The MIX is Donald Knuth's mythical computer, described in the first volume of The Art of Computer Programming, which is programmed using MIXAL, the MIX assembly language. MDK includes a MIXAL assembler (mixasm), a MIX virtual machine (mixvm) with a command line interface, a Guile-based virtual machine (mixguile), a GTK+ based GUI (gmixvm), and a mixvm-Emacs interface (mixvm.el). MDK utilities are extensible using Scheme.
MLton is a whole-program optimizing Standard ML compiler. It generates standalone executables with excellent runtime performance, supports the full SML 97 language, and has a complete basis library. It also has a fast C FFI, source-level time and allocation profiling, and many useful libraries.
Motor is a text-mode integrated programming environment for Linux. It consists of an editor with syntax highlighting, a project manager, a makefile generator, gcc, ctags, gdb, autoconf/automake and grep front-ends. CVS integration is also provided. It allows one to edit, compile, and debug programs without a need to leave the IDE, automatically check in/out files from a CVS repository and import projects into CVS, and generate distribution packages (tar.gz and RPM). The color schemes are customisable.
STklos is a free Scheme System conforming to R5RS. The implementation is based on an ad-hoc Virtual Machine. It can also be compiled as a library, so that one can easily embed it in an application. Its features include an efficient and powerful object system based on CLOS, a simple-to-use module system, implementation of the full tower of numbers defined in R5RS, and easy connection to the GTK+ toolkit. STklos is the successor of STk, a Scheme interpreter tightly connected to the Tk toolkit.
Harbour is a free, cross-platform compiler for the Xbase language. It is designed to be as compatible with CA-Clipper as humanly possible. Harbour ships with full source and makefiles, and combined with one of many C compilers will create executables which run natively on the following platforms: Linux, FreeBSD, DOS, Windows 3.x/9x/NT/W2000, and OS/2.
TinyCOBOL is an effort to bring a free COBOL compiler to Linux. It generates GNU assembler for the i386 Linux platform. A executable binary is then created using the GNU assembler and linker. The project is approaching the first beta release with many statements already implemented.