New Twiddle

components.my-component\.js

import Component from '@glimmer/component';

export default class extends Component {
}

components.my-second-component\.js

import Component from '@glimmer/component';

export default class extends Component {
}

controllers.application\.js

import Controller from '@ember/controller';
import { action } from "@ember/object";
import { tracked } from "@glimmer/tracking";

export default class ApplicationController extends Controller {
  appName = 'Ember Twiddle';
	@tracked someText = 'boom';
	@tracked model;
	@tracked trackedModel = this.model;
	@tracked trackedSomeTextBasedOnModel = this.model.someText;

	get getSomeText(){
  	return this.model.someText;
  }

	@action
	changeToBim(){
  	this.someText = "bim";
  };

	@action
	changeToBimOnModel(){
  	this.model.someText = "bim";
  };

	@action
	changeToBimOnTrackedModel(){
  	this.trackedModel.someText = "bim";
  };

	@action
	changeToBimOnTrackedSomeTextBasedOnModel(){
  	this.trackedSomeTextBasedOnModel = "bim";
  };
}

routes.application\.js

import Route from '@ember/routing/route';
import { tracked } from "@glimmer/tracking";

export default Route.extend({
  @tracked someText = "boom";
  
  model(){
  	return { someText: this.someText }
  }
});

templates.application\.hbs

<MyComponent @someText={{this.someText}} @changeToBim={{this.changeToBim}} />

<br><br><br><br>

<MySecondComponent @someTextOnModel={{this.model.someText}} @changeToBimOnModel={{this.changeToBimOnModel}} />

<br><br><br><br>

<MySecondComponent @someTextOnModel={{this.getSomeText}} @changeToBimOnModel={{this.changeToBimOnModel}} />

<br><br><br><br>

<MySecondComponent @someTextOnModel={{this.trackedModel.someText}} @changeToBimOnModel={{this.changeToBimOnTrackedModel}} />


<br><br><br><br>

<MySecondComponent @someTextOnModel={{this.trackedSomeTextBasedOnModel}} @changeToBimOnModel={{this.changeToBimOnTrackedSomeTextBasedOnModel}} />

templates.components.my-component\.hbs

someText: {{@someText}}
<br><br>
<button {{on "click" @changeToBim}}>Change to "Bim"</button>

templates.components.my-second-component\.hbs

someText on Model: {{@someTextOnModel}}
<br><br>
<button {{on "click" @changeToBimOnModel}}>Change to "Bim"</button>

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"
  }
}