drupal/composer.json

{
  "name": "drupal/drupal",
  "description": "Drupal is an open source content management platform powering millions of websites and applications.",
  "type": "project",
  "license": "GPL-2.0+",
  "require": {
    "composer/installers": "^1.0.20",
    "drupal/core": "~8.0"
  },
  "minimum-stability": "dev",
  "prefer-stable": true,
  "repositories": [],
  "config": {
    "preferred-install": "dist",
    "autoloader-suffix": "Drupal8"
  },
  "extra": {
    "_readme": [
      "This is an example file to show how a Drupal website can be managed via",
      "Composer. It does not work out of the box but requires a Git subtree",
      "split of the core directory to be added to the repositories",
      "section above."
    ]
  }
}