Here is a tar ball of PSP Software Development Kit that ZX-81 has compiled on his Linux Fedora Core 4 Destkop, and that is used to develop his homebrew programs.

Of course if you want the latest version you have to check it out from the subversion server : svn://svn.pspdev.org/psp/trunk

http://zx81.zx81.free.fr/serendipity/index.php?/archives/194-guid.html