<p><code>List of <a href="${link build-ref#labels}">labels</a>
; optional;
  <a href="#configurable-attributes">nonconfigurable</a></code></p>

<p>
The list of environments this target can be built for, <i>instead</i> of
default-supported environments.
</p>

<p>
This is part of Bazel's constraint system. See
<code><a href="#common.compatible_with">compatible_with</a></code>
for details.
</p>
