title: Composer - run scripts only in dev environment
body: <p>This is my composer.json file:</p>
  
  <pre><code>"require": {
      "php": "&gt;=5.4",
      "zendframework/zendframework": "2.*",
      "doctrine/doctrine-module": "dev-master",
      "doctrine/doctrine-orm-module": "0.*",
      "gedmo/doctrine-extensions": "dev-master"
  },
  "require-dev": {
      "phpunit/phpunit": "3.7.*"
  },
  "scripts": {
      "post-update-cmd": [
          "rm -rf vendor/Behat",
          "git clone git://github.com/Behat/Behat.git",
          "cp composer.phar Behat/composer.phar",
          "cd Behat &amp;&amp; git submodule update --init",
          "cd Behat &amp;&amp; php composer.phar install",
          "cd Behat &amp;&amp; php composer.phar require guzzle/guzzle:3.0.*",
          "mv Behat vendor/Behat",
          "ln -sf ../Behat/bin/behat vendor/bin/"
      ]
  }
  </code></pre>
  
  <p>How can I make it so the scripts are only run in the dev environment?</p>
  
  <p>Basically I want the scripts to run only when I call:</p>
  
  <pre><code>php composer.phar update --dev
  </code></pre>