Function application as a service

apply.js

function buildApply() {
  var args = Array.prototype.slice.call(arguments, 0);
  var fn = args.shift();

  // proxy function
  return function bindProxy() {
    var proxyArgs = Array.prototype.slice.call(arguments, 0);
    return fn.apply(null, args.concat(proxyArgs));
  }
}

Use case is partial application in a scenario where your target function requires access to params it wouldn't otherwise have access to.

foo.asyncMethod(key)
      .then( buildApply(proxiedMethod, biz, bazz) )