Hacker News Reader

It needs to be explicitly used. As far as I'm aware it doesn't slot in behind an existing API and magically make things better.

Got it. Are there any beginner guides yet on how to write an emacs (language) package while making use of it?

Unknown if this qualifies as "beginner guide" but the in-tree document is titled "STARTER GUIDE ON WRITING MAJOR MODE WITH TREE-SITTER": https://git.savannah.gnu.org/cgit/emacs.git/tree/admin/notes...

I hindsight I should have left out the "beginner" part. Thanks ofr pointing me in the right direction, exactly what I was looking for.