New Twiddle

components.people\.js

import Component from '@glimmer/component';
import { action } from '@ember/object';

const PEOPLE = [
  { firstName: 'Eric', lastName: 'Kelly' },
  { firstName: 'Kara', lastName: 'Luton' },
  { firstName: 'Ryan', lastName: 'Smith' },
];

export default class extends Component {
  PEOPLE = PEOPLE;

  @action
	buildFullName(person) {
    return [person.firstName, person.lastName].join(' ');
  }
}

controllers.application\.js

import Controller from '@ember/controller';

export default class ApplicationController extends Controller {
  appName = 'Ember Twiddle';
}

templates.application\.hbs

<h1>Welcome to {{this.appName}}</h1>

{{outlet}}

<People />

templates.components.people\.hbs

<h2>First names:</h2>

<ul>
  {{#each this.PEOPLE as |person|}}
    <li>{{person.firstName}}</li>
  {{/each}}
</ul>

<h2>Full names</h2>

<ul>
  {{#each this.PEOPLE as |person|}}
    <li>{{compute this.buildFullName person}}</li>
  {{/each}}
</ul>

twiddle\.json

{
  "version": "0.17.1",
  "EmberENV": {
    "FEATURES": {},
    "_TEMPLATE_ONLY_GLIMMER_COMPONENTS": false,
    "_APPLICATION_TEMPLATE_WRAPPER": true,
    "_JQUERY_INTEGRATION": true
  },
  "options": {
    "use_pods": false,
    "enable-testing": false
  },
  "dependencies": {
    "jquery": "https://cdnjs.cloudflare.com/ajax/libs/jquery/3.5.1/jquery.js",
    "ember": "3.18.1",
    "ember-template-compiler": "3.18.1",
    "ember-testing": "3.18.1"
  },
  "addons": {
    "@glimmer/component": "1.0.0",
    "ember-composable-helpers": "4.2.2"
  }
}