The following is an excerpt from http://wiki.freebsd.org/IvanVoras/pkg_patch :

 * pkg_patch: Project start + patch generation step (for individual packages): 2 weeks
 * pkg_patch: Patch application step: 2 weeks
 * pkg_patch: wrapper or built-in function for generating patches to multiple packages: 1 week
 * Update infrastructure: define the format of the list of updates, generate a test set: 1 week
 * -- midterm --
 * pkg_patch: wrapper or built-in function for fetching the list of packages needing the updates, fetching the patches and applying them: 4 weeks 

