For the first patch, I added the -n flag to gzip in order to prevent the md5sum problem. The apply-delta script is not as efficient as it could be. There is an extra gunzip+gzip step that could be avoided if we create a delta on the .tar rather than the .tar.gz. Doing so would complicate makepkg a bit, so I stuck with the extra step. For the second patch, I created a second function, create_xdelta_latest, which creates a delta for the latest package with a given package name. I did this because otherwise a delta would be created for every package given on the command line which is annoying for me because I use *.pkg.tar.gz. Problems: * gzip upgrade could produce different md5sums - could have had the problem before if a zlib upgrade did the same thing * all delta files that currently exist will not work (probably not a problem)