Cannot find module ‘gulp’
<p>When I run the <code>ionic build android</code> command, I get the following error:</p>

<pre><code>WARN: ionic.project has been renamed to ionic.config.json, please rename it.
Uh oh! Looks like you're missing a module in your gulpfile:
Cannot find module 'gulp'

Do you need to run `npm install`?
</code></pre>

<p>I have already tried running this command:</p>

<pre><code>npm install --save-dev gulp
</code></pre>

<p>But I am still getting the same error. Am I missing something here?</p>