A common pattern for building static sites on GitHub Pages (or similar) is to just trigger a new build every time there’s a change in the repository. This is very straightforward and well-tested, and works until you want to also trigger builds when something changes outside the repo. Then you run into some issues — but the solution, which took me some time to hunt down, turns out to be simple. The trick is specifying the right ref in your build workflow, and I explain why below.
