I find cross-references to be a big win. I've taken to using `@@{subject}` syntax as anchors and `^^{subject}` as references, anywhere in comments, docs, etc,

I find cross-references to be a big win. I've taken to using `@@{subject}` syntax as anchors and `^^{subject}` as references, anywhere in comments, docs, etc, within a single repository. Then I set up tooling that checks that every reference has a (single) corresponding anchor, and tooling that surfaces in github PRs the other relevant bits when an anchor or reference shows up in the (changed or context) lines of a diff.