How extend task provided by plugin?

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1

I have kotlin2js plugin with task compileKotlin2Js. I configure it like this:

val compileKotlin2Js: Kotlin2JsCompile by tasks
compileKotlin2Js.kotlinOptions {
    main = "call"
    outputFile = "${projectDir}/build/app.js"
}

Now I want to create similar task, but with other kotlinOptions. For example:

.kotlinOptions {
    main = "noCall"
    outputFile = "${projectDir}/build/lib.js"
}

How to do it?