Libcwd is a full-featured and well-documented library that assists C++ developers with debugging their applications. It includes support for ostream-based debug output, custom debug channels and devices, memory allocation debugging, run-time sourcefile:linenumber information, and demangled type names of variables. It is thread-safe.
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.
Code Medic provides access to the power of gdb with an intuitive front end. It currently supports opening multiple source windows at once, setting/clearing breakpoints while the program is running, watching variables change in the variable tree as you step through code (even with nested structs), text searching through source, and integration with Code Crusader to provide a rapid, efficient develop-debug cycle.
MIT/GNU Scheme is an implementation of the Scheme programming language, providing an interpreter, compiler, source-code debugger, integrated Emacs-like editor, and a large runtime library. MIT/GNU Scheme is best suited to programming large applications with a rapid development cycle. Recent versions of the system are supported on the following platforms: GNU/Linux, *BSD, OS/2, and Windows.
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.
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.
Setedit is a text editor specially designed for programmers. It has a nice interface with mouse support, menus and windows (text mode). The editor is a very good choice for people with DOS background, especially people accustomed to Worstar and Borland editors. The editor has overlapped windows so you can see more than one file at the same time, configurable syntax highlighting, macros, rectangular selection, block indentation, as well as customizable keyboard shortcuts and menus.
spim is a self-contained software simulator for running R2000/R3000 assembly language programs. It reads and can immediately execute files containing assembly language code. spim also provides a debugger and simple set of operating system services. spim provides both a simple, textual interface and a fancier, graphical interface. The package includes complete source code and documentation.