(posting here because I have no idea where else to submit this) We have already two different eclasses to take care of updating the sources of various packages for particular problems: libtool.eclass with elibtoolize and gnuconfig.eclass with gnuconfig_update. While the latter is now mostly handled by econf, there are more than a few packages that can't be ported to use econf for some reason. elibtoolize is routinely dropped out of packages by mistake, and also does not allow to have "experimental" patches: a change to the patchsets will apply to all packages, no matter their keywording status. Additionally there are other common operations often applied to packages: kde.eclass updates the admin/ directory for (some) packages to let them work with newer versions of autotools and similar issues, FreeBSD has to fix gnulib sources when they contain given patterns, and so on. The autoepatch project was created to solve this issue, allowing "plug-in" like scripts that apply patchsets or execute given functions over the sources to make the needed changes. While the base of this is present in SVN, it hasn't been worked on for about an year by now. This program also has to be integrated with Portage so that it's always executed between src_unpack and src_compile.
No progress, last commit in the autoepatch repo is from 2006.