val javaToolchains = project.extensions.getByType<JavaToolchainService>()
    val javaPluginExtension = project.extensions.getByType<JavaPluginExtension>()
    javaCompiler.set(javaToolchains.compilerFor(javaPluginExtension.toolchain))
  }

  val targetDir = compileKotlinTask.destinationDirectory.dir("../java9")
  val sourceDir = file("src/jvmMain/java9/")

  // Use a Java 11 compiler for the module info.
  javaCompiler.set(project.javaToolchains.compilerFor { languageVersion.set(JavaLanguageVersion.of(11)) })

  // Always compile kotlin classes before the module descriptor.
  dependsOn(compileKotlinTask)

  // Add the module-info source file.
  source(sourceDir)