Packages which do not link to libsystemd but only rely on e.g. libudev needn't be rebuilt but only get their description altered. One can check whether an elf file links against a lib like
this (github gist).
It would also be easy to automate the check and conversion of uninstalled pkgs on specific libs like libsystemd, libudev and the like (e.g. download file, extract, check -> substitute, pack). So we could create a list of packages and the dependencies that must be substituted do mitigate a fake systemd dependency. Then users could check packages with systemd deps they encounter and submit them with the names of the substitution libs if the check was successful (in the way that systemd is not really needed). The packages in this list could become converted and in the course of this checked automatically (e.g. by
travis-ci), and finally be distributed in a special repository (perhaps easier to handle than integration with regular repo).
The substitution list could be a git repo with a file mapping libraries to lib packages, then one dir per package and one file per version containing the substituting libs.
Then there could be per-package checksum files (like the Manifests in the Gentoo portage tree)Git has checksums.
I think this would be a community driven, low maintenance process for converting the packages that are really used.
What is your opinion on this?