file.txt

var myApp = $.sammy(function() {

  this.helpers({
    loadIndex: function() {
      // you can do everything you would do in a route here.
    }
  });

  this.get('#/index', function() {
    this.loadIndex();
  });
  
})

// overriding:

myApp.helpers({
  loadIndex: function() {
    // new index
  }
})

// or as a plugin

var overrideApp = function(app) {
  app.helpers({
    loadIndex: function() { ... }
  });
}; 

myApp.use(overrideApp);