title: In a MVC system, where I put my classes that are not part of MVC?
body: <p>For example: I have a session class, a message class, a CRUD class, in which folder I put them?</p>
  <p>my folder structure is:</p>
  <pre><code>app/    &lt;-- MVC logic
  config/ &lt;-- config files
  core/   &lt;-- core files of application, such as init
  public/ &lt;-- index and assets
  vendor/ &lt;-- for composer packages
  </code></pre>