README.adoc for the picocli-codegen subproject states (chapter 2.1.4. Kotlin Projects Using Maven, line 161):
JetBrains' Kotlin Examples repository has a complete example complete sample project showing the use of Kotlin, Maven and Dagger.
The link given in this paragraph is dead and should be replaced or removed. I did a quick search, but couldn't find either the original source nor an appropriate alternative link. Hopefully you have more luck!