An interactive Beamline Matching application has been coded using internally developed beamline and automatic differentiation class libraries. Various freely available components were used. In particular, the user interface is based on FLTK, a C++ toolkit distributed under the terms of the GNU Public License (GPL).
The result is an application that compiles without modifications under both X-Windows and WIN32 and offers the the same look and feel under both operating environments. In this paper, we discuss some of the practical issues that were confronted and the choices that were made. In particular, we discuss object-based event propagation mechanisms, multithreading, language mixing and persistence. wally%