Write planning-modular.txt

Would work on this issue in next week

I am unassigning the task for now so that if someone else would like to pick this can move ahead!

will work on this issue

Jennifer, Joe: you have a particular d.o. docs page or external blog post or tutorial in mind that could serve as basis for this topic??

Yes please ;)

Nice. This seems like a pretty challenging topic to get right, and we're on the right track for sure. Here are my thoughts after reading it over a couple of times.

I think it would be good to include a reference to structure-view-modes.txt here. View modes + views module are a super powerful way of implementing this idea of "modular" pages.

Another example of this idea that I feel like we could illustrate better here is the whole edit once, update in many places automatically. So for example in our use-case we've got a vendor content type, and a recipe content type (see also structure-adding-reference.txt). Using this, you could create a block/view that displays the vendor's information on every recipe page. Since it's dynamically pulling that content in, you can update it in one place, and the phone number (or maybe more appropriate would be market stall number) is updated everywhere right away. Which, might actually be covered by structure-reference-fields.txt, in which case maybe we should just include a link to that, and maybe add an item to the examples list on this topic that says something like, "Display information about the vendor who submitted the recipe being viewed."

Smaller sections of pages can also be generated as composites. For instance,
your site could display a list of the most recently added recipes in a
sidebar. Once that is set up, the list would automatically be updated whenever a
new recipe is added to the site, without having to go edit another page to keep
the list current.

Maybe this chunk could be adjusted a bit to reflect this idea:

Smaller sections of pages can also be generated as composites. For instance,
your site might display a vendor profile page with two columns, one contains the information
from the vendor content entity, and the other contains a list of the recipes that the vender has added.
Once that is set up, the list would automatically be updated whenever a vendor adds a new recipe to the site,
without having to go and edit the vendor's profile page to keep the list current.

I think the gist of it is there, it just wasn't immediately obvious to me. My first time reading this I was sort of like, how is this any different than views-concept.txt? So I think maybe we can do a better job of explaining that we're talking about using content entities, blocks, views, and maybe other elements to compose dynamic pages. Or something like that.

Is that helpful feedback? If not, I can try and think through this a bit more.

This definitely seems like a "tie all your existing knowledge together" topic.

Content looks good. Needs an attribution and then I can go ahead and get it committed. Thanks.