Drupal Composer example

composer.json

{
    "name": "drupal-composer/drupal-project",
    "description": "Project template for Drupal 8 projects with composer",
    "type": "project",
    "license": "GPL-2.0+",
    "authors": [
        {
            "name": "",
            "role": ""
        }
    ],
    "repositories": [
        {
            "type": "composer",
            "url": "https://packagist.drupal-composer.org"
        },
        {
          "type": "package",
          "package": {
            "name": "drupal/pathauto",
            "version": "dev-master",
            "type": "drupal-module",
            "source": {
              "url": "https://github.com/md-systems/pathauto.git",
              "type": "git",
              "reference": "e5a14769e1f8340b6f0e1e3384c6c8120ea5c79d"
            }
          }
        },
        {
          "type": "package",
          "package": {
            "name": "drupal/gist_embed",
            "version": "dev-master",
            "type": "drupal-module",
            "source": {
              "url": "https://github.com/jmolivas/gist_embed.git",
              "type": "git",
              "reference": "8c69c0ed119194831468e18738e45c6c6a2edbd9"
            }
          }
        },
        {
          "type": "package",
          "package": {
            "name": "drupal/casper",
            "version": "dev-master",
            "type": "drupal-theme",
            "source": {
              "url": "https://git.drupal.org/project/casper.git",
              "type": "git",
              "reference": "8.x-1.x"
            }
          }
        }
    ],
    "require": {
        "composer/installers": "^1.0.20",
        "cweagans/composer-patches": "~1.0",
        "drupal/core": "8.0.*",
        "drush/drush": "~8.0",
        "drupal/big_pipe":  "~8.1",
        "drupal/admin_toolbar": "~8.1",
        "drupal/ctools":  "~8.1",
        "drupal/token":  "8.x-1.x-dev",
        "drupal/disqus":  "~8.1",
        "drupal/pathauto": "dev-master",
        "drupal/gist_embed": "dev-master",
        "drupal/casper": "dev-master"
    },
    "require-dev": {
        "behat/mink": "~1.6",
        "behat/mink-goutte-driver": "~1.2",
        "jcalderonzumba/gastonjs": "^1.1@dev",
        "jcalderonzumba/mink-phantomjs-driver": "dev-master#10d7c48c9a4129463052321b52450d98983c4332",
        "mikey179/vfsStream": "~1.2",
        "phpunit/phpunit": "~4.8",
        "symfony/css-selector": "2.7.*"
    },
    "minimum-stability": "dev",
    "prefer-stable": true,
    "scripts": {
        "post-install-cmd": [
            "sh ./scripts/composer/post-install.sh"
        ]
    },
    "extra": {
        "installer-paths": {
            "web/core": ["type:drupal-core"],
            "web/modules/contrib/{$name}": ["type:drupal-module"],
            "web/profiles/contrib/{$name}": ["type:drupal-profile"],
            "web/themes/contrib/{$name}": ["type:drupal-theme"],
            "drush/contrib/{$name}": ["type:drupal-drush"]
        }
    }
}

@jmolivas change line 84 to "post-install-cmd": ["sh ./scripts/composer/post-install.sh"]. Otherwise you will get this error.

thanks fixed.