Hi Kelly

>> The code from that is in
>>
>> https://github.com/latex3/latex3/tree/master/xpackages/xfrontm
> I’m currently reading through this and I think I have some related ideas;
> although xfrontm is more evolved than my initial thoughts.

well, I can't honestly claim that I all of that is needed or in any way 
in the form I would do it now if I would redo it (haven't looked at it 
for a long time). But it was certainly representing the thoughts back 
then and the complexity and interfaces are due to looking at a huge 
number of different front matter requirements and trying to abstract 
from them in  a useful way.

Still, there might be stuff missing or stuff that is over the top.


>> My architecture vision talk in India gives a good overview on that
>>
>> https://www.latex-project.org/publications/indexbyyear/2011/
> I’ve watched this talk a couple of times now and am very excited by its ideas
> and the possibilities it offers. I’ll keep this in mind as I work on the class.

Eventually I really want to get back to that, after all the code is 
there and only waiting to be updated to the latest expl3 versions and I 
think something along those lines is kind of the right thing make a big 
leap as far as design interfaces are concerned.

frank