Empty app - white screen - main.js missing

I have an empty sidemenu app.
On ionic serve everything goes as expected but then white screen appears.
There is no error but build.js is missing.
Any thoughts ?

ionic info

Your system information:

ordova CLI: 6.5.0
Ionic Framework Version: 2.0.0-rc.5
Ionic CLI Version: 2.2.1
Ionic App Lib Version: 2.2.0
Ionic App Scripts Version: 1.0.0
ios-deploy version: Not installed
ios-sim version: Not installed
OS: Windows 10
Node Version: v6.9.4
Xcode version: Not installed

    >ionic serve

> ionic-hello-world@ ionic:serve P:\!IONIC\testapp
> ionic-app-scripts serve "--v2" "--address" "0.0.0.0" "--port" "8100" "--livereload-port" "35729"

[14:57:54]  ionic-app-scripts 1.0.0
[14:57:55]  watch started ...
[14:57:55]  build dev started ...
[14:57:55]  clean started ...
[14:57:55]  clean finished in 1 ms
[14:57:55]  copy started ...
[14:57:55]  transpile started ...
[14:57:58]  transpile finished in 2.60 s
[14:57:58]  webpack started ...
[14:57:58]  webpack finished in 148 ms
[14:57:58]  sass started ...
[14:57:58]  copy finished in 2.77 s
[14:57:58]  sass finished in 616 ms
[14:57:58]  build dev finished in 3.39 s
[14:57:58]  watch ready in 3.51 s
[14:57:58]  dev server running: http://localhost:8100/

package.json

{
  "name": "ionic-hello-world",
  "author": "Ionic Framework",
  "homepage": "http://ionicframework.com/",
  "private": true,
  "scripts": {
    "clean": "ionic-app-scripts clean",
    "build": "ionic-app-scripts build",
    "ionic:build": "ionic-app-scripts build",
    "ionic:serve": "ionic-app-scripts serve"
  },
  "dependencies": {
    "@angular/common": "2.2.1",
    "@angular/compiler": "2.2.1",
    "@angular/compiler-cli": "2.2.1",
    "@angular/core": "2.2.1",
    "@angular/forms": "2.2.1",
    "@angular/http": "2.2.1",
    "@angular/platform-browser": "2.2.1",
    "@angular/platform-browser-dynamic": "2.2.1",
    "@angular/platform-server": "2.2.1",
    "@ionic/storage": "1.1.7",
    "ionic-angular": "2.0.0-rc.5",
    "ionic-native": "2.2.11",
    "ionicons": "3.0.0",
    "rxjs": "5.0.0-beta.12",
    "zone.js": "0.6.26",
    "sw-toolbox": "3.4.0"
  },
  "devDependencies": {
    "@ionic/app-scripts": "1.0.0",
    "typescript": "2.0.9"
  },
  "cordovaPlugins": [
    "cordova-plugin-whitelist",
    "cordova-plugin-console",
    "cordova-plugin-statusbar",
    "cordova-plugin-device",
    "cordova-plugin-splashscreen",
    "ionic-plugin-keyboard"
  ],
  "cordovaPlatforms": [],
  "description": "testapp: An Ionic project"
}

image

Thanks