diff --git a/docs/next/testing.html b/docs/next/testing.html
index 1d77214af84..c15208217f2 100644
--- a/docs/next/testing.html
+++ b/docs/next/testing.html
@@ -35,7 +35,7 @@ $ npm run flow
 javac <span class="hljs-number">1.8</span><span class="hljs-number">.0</span>_111
 </code></pre>
 <p>The version string <code>1.8.x_xxx</code> corresponds to JDK 8.</p>
-<p>You also need to install the <a href="https://buckbuild.com/setup/install.html">Buck build tool</a>.</p>
+<p>You also need to install the <a href="https://buckbuild.com/setup/install.html">Buck build tool</a>. Note that brew may not install the version needed to run the tests. For best results, use the same version as the GitHub builds, which can be found in the <code>.circleci</code> folder in the root of the repo.</p>
 <p>To run the Android unit tests:</p>
 <pre><code class="hljs">$ cd react-native
 $ ./scripts/run-android-local-unit-tests.sh