ironment variables</a>
    section of this page for more information on passing variables from the host
    machine to the rule.
  </p>
</section>

<section class="mt4">
  <h2 class="title-2" id="srcs">Sources</h2>

  <p>
    Sources are the inputs to your rule - typically source code, but like any
    other inputs, they can also be build labels. This is defined in the
    <code class="code">srcs</code> argument.
  </p>

  <p>
    All sources are linked into the build directory - for performance reasons
   