Chicken is a Scheme compiler that translates most of R5RS Scheme into relatively portable C. It supports fully general tail-call recursion, first-class continuations, and has a very flexible and efficient interface to C and C++. Chicken implements several extensions to the Scheme language: lightweight threads, pattern matching macros, dynamic loading of compiled code, and various object-oriented paradigms, such as TinyCLOS, and others. The library system includes hundreds of convenient modules for practical use.
The Free Finite Element Package is a modular collection of C libraries which contain numerical methods required when working with linear and quadratic finite elements in two dimensions. FFEP works on GNU/Linux and is portable to every system where MEML (i.e. LAPACK and BLAS) are available. The goal of FFEP is to provide basic functions for approximating the solution of elliptic and parabolic partial differential equation in two dimensions with Dirichlet and Neumann boundary conditions.
Pre Make Kit (PMK) aims to be a BSD alternative to GNU autoconf, GNU libtool, and pkg-config. It uses data files instead of scripts to limit the spreading of trojans in software packages. It's designed to be easy to use for users and developers. For better portability and efficiency, all of the components are written in C. Requirements are a POSIX system, a C compiler, a POSIX shell, and a make tool.