Aubit 4GL compiler is a programming language based on (and compatible with) Informix-4GL. It provides an easy way to generate screen/form based programs, since statements for handling Windows, Forms, Menus, SQL, and similar are built-in. With support for SQL statements forming an intrinsic part of the language, it's especially suitable for developing database-oriented applications. Database connectivity is provided for PostgreSQL, MySQL, Informix, and others via ODBC. It supports both ncurses (console mode) and GTK+ (GUI mode) output.
'App' is a preprocessor for C++ that accepts as input arbitrary C++ code that may contain embedded constructs for specifying algebraic data types and associated pattern matching operations, and produces as output the same code with all such constructs translated to normal C++. What app essentially does is provide for C++ pretty much the same capabilities that functional languages have regarding algebraic types. 'Applib' is the associated runtime library that supports the core run time requirements of the translated code, and which provides additional utilities (applib is covered by the LGPL).
Synopsis is a multi-language source code introspection tool that provides a variety of representations for the parsed code to enable further processing such as documentation extraction, reverse engineering, and source-to-source translation. It provides a framework of C++ and Python APIs to access these representations and allows Processor objects to be defined and composed into processing pipelines, making this framework very flexible and extensible.
VFGEN is a program that takes a specification of a vector field (in other words, a system of differential equations) and generates source code for a wide variety of ODE solvers and other numerical tools. It includes a command for generating C code to be used with the CVODE solver.
Yacas is a general purpose, easy to use Computer Algebra System (a CAS is a program that can be used to do symbolic manipulation of mathematical expressions). It is built on top of its own programming language designed for this purpose, in which new algorithms can easily be implemented. In addition, it comes with extensive documentation on the functionality implemented and methods used to implement them.