Example Adaro/Dustjs additional helpers configuration

example-adaro-config.json

  "view engines": {
    "js": {
      "module": "engine-munger",
      "renderer": {
        "method": "js",
        "arguments": [
          { 
            "cache": true,
            "helpers": [
              { 
                "name": "dustjs-helpers",
                "arguments": []
              },
              {
                "name": "./lib/helpers/cdn",
                "arguments": [
                  { 
                    "cdn": "cdn$.xyz.com",
                    "arity": 4
                  }
                ]
              }
            ]
          },
          {
            "views": "config:express.views",
            "view engine": "config:express.view engine",
            "specialization": "config:specialization",
            "i18n": "config:i18n"
          }
        ]
      }
    }
  },

Worth noting, perhaps, that anything that doesn't take arguments (other than the implicit dust) such as ...

{ 
  "name": "dustjs-helpers",
  "arguments": []
}

... can be replaced with ...

"dustjs-helpers"

... if you don't mind the mix of objects and strings in your helpers array.