Groovy plugin deletes .classes from build/classes which are not used by groovy classes

If use kotlin with groovy (

groovy plugin deletes some kotlin .class files from build/classes

so it makes impossible to mix groovy with kotlin cause groovy plugin ignores source sets

Question: is it possible to configure groovy plugin to keep files in build/classes intact ?

p.s: kotlin plugin invokes: compileKotlin compileJava - up to date ------------------------------------ compileGroovy - deletes some Kotlin .classes - compilation error as a consequence since ClassNotFoundException happens

Can you provide a simple test case to reproduce this?