Add Scala Compiler Plugins Using a Custom Config

build.gradle

tasks.withType(ScalaCompile){
    // Map plugin jars to -Xplugin parameter
    List<String> parameters =
    configurations.scalaCompilerPlugin.files.collect {
        '-Xplugin:'+ it.absolutePath
    }

    // Add existing parameters
    List<String> existingParameters = scalaCompileOptions.additionalParameters
    if (existingParameters) {
        parameters.addAll(existingParameters)
    }

    // Add whatever flags you typically add
    parameters += [
            '-language:implicitConversions',
            '-language:higherKinds'
    ]
    
    // Finally set the additionalParameters
    scalaCompileOptions.additionalParameters = parameters
}