To get the right dependencies in pom.xml, I create a basis, walk :libs to find libs that have poly/* libs in the :dependents (and also have :mvn/version) and then compute a new basis with those (top-level transitive) deps as :extra {:deps ...}

Then I update the :libs from that basis to have just :mvn/version style libs (so that write-pom doesn't complain about skipping coordinates for all the :local/root deps!).

And the copy-dir step takes the :classpath-roots from that basis and filters just the directories (which should be the src and resources for the project itself plus all the src/`resources` from all the :local/root deps as well).

(this last part is essentially the default behavior of depstar when building JAR files, but you can tell it to just use :paths instead -- which is sort of the "default" recipe if you follow the tools.build guide)

Confirming that I'm on the right track with creating a basis with the "1st-level" deps (top-of-the-transitive deps) for write-pom would be good -- that part felt really clunky.

sure?

I realized after I posted this that I need to solve this in more general terms for anyone trying to build library JARs from Polylith projects.

depstar gets it wrong -- it copies the transitive :local/root source etc OK but it doesn't bring across those 1st-level external deps into pom.xml 😞