How to build .coffee into .js without wrapper function

I'm using 'coffee-script` npm package:

var coffee = require('coffee-script');
var source = coffee.compile('target.js');

and I have compiled js inside of source variable. But it also wrapped into self-invoked function. I don't need that invocation, b/c I'm using Webmake for managing dependencies, that wrap each file.. and I will have 2 invocations.

"some.js": function (exports, module, require) {
  (function() {
    var n;
    n = 5;
    alert("hello world " + n);
  }).call(this);
}

As you can see, I don't need coffee-script invocation. P.S. I can't find any documentation about CoffeeScript.compile options that is second argument for .compile. Can you provide me also that information. thanks.