SoftRelTools use GNU Make for building libraries and executables. The file GNUmakefile, in the area where the gmake command is given, tells GNU Make what to build. The developer introducing a new package, or the user trying to link an executable, needs to modify simple makefiles described in section D.1. Developers, code librarians, and code managers will want to be aware of the makefiles discussed in section D.2, but should not need to modify them.