Indeed, the "Developing & Extending" box welcomes improvements.
My personal point of view is thinking "What would I like to achieve when going to https://www.mediawiki.org/w/index.php?title=MediaWiki&oldid=2301969 ?"
Which is pretty much T653: Refresh the mediawiki.org homepage (which is as Epic as it could get).

I would not necessarily want to throw yet another link into the mix but also potentially rethink the sidebar (to start somewhere) and make people find relevant developer resources via an improved version of "How to contribute". Which currently throws a lot of non-self-explanatory colorful links at me and does not explain what I can do. See T169599: Sort out concept for overview/entrance pages targeting our developer audience.

Currently

• the sidebar has an item "Contribute".
• the "New opportunities" (what?!) has an item "Other ways to contribute..."
• the "Development" section in the sidebar links to random infrastructure. I don't see how that is helpful, compared to a guide how to use that infrastructure.

I would not necessarily want to throw yet another link into the mix

Agreed! Retook a look at the page, and realized, growing another tulip in the field will not help. Even though revamping the MediaWiki homepage is a distant dream right now, I will think about some ideas for re-touching a bit all the sections that are all taking us to sometimes same & sometimes confusing venues. And, the "Development" sidebar.. the one in small fonts that my eyes behind big glasses were not able to recognize yet, could indeed be the first small, easy task of this task :P