c)</li>
<li>per-user config file (~/.npmrc)</li>
<li>global config file ($PREFIX/etc/npmrc)</li>
<li>npm builtin config file (/path/to/npm/npmrc)</li>
</ul>
<p>All npm config files are an ini-formatted list of <code class="language-text">key = value</code>
parameters.  Environment variables can be replaced using
<code class="language-text">${VARIABLE_NAME}</code>. For example:</p>
<div class="gatsby-highlight" data-language="bash"><pre class="language-bash"><code class="language-bash">prefix <span class="to