Is it possible to write a custom settings plugin using precompiled scripts? If so does anyone have any example references? In particular, I'm looking to write one to share common build cache settings.

Yes, you have to name it: *.settings.gradle[.kts] https://github.com/hfhbd/ComposeTodo/blob/main/gradle/build-logic/src/main/kotlin/MyRepos.settings.gradle.kts

And it can't be done in

buildSrc

, only an included build or published. And the include must be inside

pluginManagement { ... }

.

That did the trick, thank you both! Luckily I plan to publish it so no issues there.