One of GPT's major strengths is that it allows packages to be built on any UNIX platform that has the appropriate GPT prerequisites installed. Once your software package becomes a part of a distribution of GPT packages, user expectations will include being able to build it on all sorts of UNIX platforms. GPT does not provide an answer for this itself but ti is compatible with tools such as GNU autoconf and GNU libtool which provide some portability support. The last packaging chapter will discuss how to use these tools.