Because VR Juggler has always been a cross-platform tool, we have had the need for a cross-platform way to build it. The VR Juggler 1.0 build system achieved this to a limited degree, and Doozer++ goes a step further toward true platform independence. At this time, Doozer++ makes use of software utilities found on all modern operating systems. The list of utilities includes m4(1), sh(1), Perl, Autoconf, and GNU make. We have avoided the use of platform-specific tools because it is all too easy for the platform-specific parts of a build system to get out of sync with each other. Furthermore, we have tried to avoid the use of platform-specific code whenever possible. This is a more difficult goal to achieve, but later sections will address the extent to which platform-specific code can be reduced.