The QNAP QDK is used for packaging and installing pre-built binary packages for the QNAP line of network attached storage devices. qpkg is their custom packaging format, because the many existing binary packaging standards were apparently not good enough. The qdk is licensed under the GNU Public License version 2 (see COPYING).
See this pdf cleverly wrapped in a zip file and version-controlled via a stickied forum post for some explanation of the packaging format.
I extracted the qdk files manually by inspecting the shell script packed onto the front of the qdk qpkg. For more info on how this was done see this blog post.
Please file all bugs on the QNAP forums: http://forum.qnap.com/
why host this code on github?
I do not maintain the qdk nor do I use it. I posted the source to github because it is GPL licensed and I could not find the source code easily available anywhere. The only way to get the source is to install the qdk qpkg. It is a bootstrapping problem: to install the qdk you need the qdk installed. This possibly constitues a GPL violation and it seriously annoyed me, hence this github project.