What you are talking about seems to be templates? I can’t recall when he was talking about it, but Uberlord have afaik implemented something like that in OpenRC. He had en example that looked something like your example of what you where looking for, but OpenRC usually still uses the “common” #/bin/sh format.

But at template system could be nice, something like portages eclasses you can choose between and after that you only have some variables to set (like the one you demoed) and from that on only have to change the “defaults” for that template. Or do not use a template and have everything implanted from scratch if you want/need, thus allowing modules of the “current” sort.

This is what I meant with the fourth entry in my list: an easy way to choose between alternatives without having to write a new eselect module for each. I also hope it would be also without having to list all the alternatives inside the module, letting the implementations themselves install a datafile saying “I’m here, you can choose me”.

This would be why we have eselect libraries, as well as modules. Quite why no-one ever used them is beyond me…

This is what I wrote skel.bash for. It currently is written to do stuff in lib* only, but it could probably be modified fairly easily to do what you want.