New Twiddle

application.controller.js

import Ember from 'ember';

export default Ember.Controller.extend({
  appName: 'Ember Twiddle',
  
  variable: 2,
  
  double: Ember.computed('variable', {
    get() {
      return this.get('variable') * 2;
    },
    
    set(key, value) {
      return value;
    }
  })
});

application.template.hbs

<h1>Welcome to {{appName}}</h1>
<div>Variable: {{variable}}</div>
<div>Double: {{double}}</div>

{{input value=variable}}
{{input value=double}}

twiddle.json

{
  "version": "0.5.0",
  "EmberENV": {
    "FEATURES": {}
  },
  "options": {
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/1.11.3/jquery.js",
    "ember": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.2.0/ember.debug.js",
    "ember-data": "https://cdnjs.cloudflare.com/ajax/libs/ember-data.js/2.2.0/ember-data.js",
    "ember-template-compiler": "https://cdnjs.cloudflare.com/ajax/libs/ember.js/2.2.0/ember-template-compiler.js"
  }
}