Gradle no plugin solution for building fat jars

gradle.build.kts

val fatJar = task<Jar>("fatJar") {
    with(tasks["jar"] as CopySpec)
    duplicatesStrategy = DuplicatesStrategy.INCLUDE
    from(configurations.runtimeClasspath.get().map {
        if (it.isDirectory) it
        else zipTree(it)
    })
    manifest {
        attributes["Main-Class"] = "io.ktor.server.netty.EngineMain"
    }
}

tasks.getByName("build")
    .dependsOn(fatJar)

https://stackoverflow.com/questions/41794914/how-to-create-the-fat-jar-with-gradle-kotlin-script