I have a single page web app which uses backbone in the client, and node (Sails) on the server.

I currently use lodash.underscore as the template engine in the client, and kiwi on the server.

I wish to implement pushstate with progressive enhancement. i.e. the client and server will share the same template files. 

This means they'll need to use the same template engine; I have decided to go with underscore/lodash.

Within Sails config\views.js it implies you can use underscore as the template engine. Problem is I cant work out how to do this. I've included it in my package.json and set 

```
'engine': 'underscore'

```

I then get an error when firing up my app - "callback function required at Function.app.engine"

If I set the engine to 'kiwi', 'jade', 'ejs' etc then it'll work.

Any idea's what I'm doing wrong?