title: How can I install a specific node.js version on a PHP container on Travis CI?
body: <p>For a Laravel project I use Travis Ci with the language option as PHP. Besides PHP I want to do some Node JS testing. The default installed version of Node JS does not meet my requirements. How can I specify the version of Node JS in my config file?</p>
  
  <p>I have tried the following. But unfortunately, that does not work.</p>
  
  <pre><code>language: php
  
  php:
    - '7.0'
    - '7.1'
  
  node_js:
    - '6.10'
  </code></pre>