Project import generated by Copybara.
PiperOrigin-RevId: 362153315
Change-Id: Id591e2d5bfd457b9a285b9e3c9a99a1b720a96b0
diff --git a/docs/testing.md b/docs/testing.md
index f757002..0832b44 100644
--- a/docs/testing.md
+++ b/docs/testing.md
@@ -24,6 +24,10 @@
and
[`Parameterized`](https://junit.org/junit4/javadoc/4.12/org/junit/runners/Parameterized.html).
+NOTE For best practices on writing libraries in a way that makes it easy for end
+users -- and library developers -- to write tests, see the
+[Testability](testability.md) guide.
+
### What gets tested, and when
We use the
