Cassowary/C++ needs to be compiled using a modern C++ compiler. At one time or another, it has compiled using: o egcs-1.0.1, egcs-1.0.3, egcs-1.1b, gcc-2.8.1, gcc-2.95.2 o Visual C++ 5.0 Cassowary/Java was developed using Sun's JDK-1.1.3, ported to Linux More recent versions should work fine, and it has been tested with JDK-1.2pre2. The included Makefiles depend upon features of GNU Make. See: ftp://ftp.gnu.org/pub/gnu/ for a version that you can build. To build the c++/qdemos/QuadDemo application, you'll need TrollTech's Qt widget set for X11, available from: http://www.troll.no/dl/qtfree-dl.html See also the Scwm (Scheme Constraints Window Manager) web page for a use of Cassowary in a substantial application: http://scwm.mit.edu/scwm/