title: Haskell Stack ghci flags
body: <p>Basically, I am trying to achieve the following:
  <code>
  stack ghci --flag proj:dev
  </code>
  but it seems that flag is not valid for ghci, only for <code>build</code>.</p>
  
  <p><strong>How can I achieve this?</strong>  If possible </p>
  
  <p>*Notes:<br>
  <code>proj</code> is a cloned yesod-postgres template, I do not want to use yesod devel since I find it painfully slow. And I already have ghci to watch changes and notify browser-sync.</p>