This targets jvm 1.8 with source compatibility for jdk15

build.gradle.kts

https://gist.github.com/1820100ed3d8...23e72dea95fc7c

settings.gradle.kts
https://gist.github.com/4c8bed452460...75b2ccea9c1f63

Here are some samples you can reference:
https://github.com/gradle/kotlin-dsl...kotlin-project

Of course, you can change the names to whatever you wish.
Using this will remove the need to keep .jars in your 'lib' (or w/e) folder.

Successful usage:
Attached image