diff --git a/src/_secureaccesstokenauthorizer/tests/test_plugin.py b/src/_secureaccesstokenauthorizer/tests/test_plugin.py
index 4c62ca74b70ae6e75db4ce396abdc656d825d5fd..2018d51207d32f08c612ec09d1bc9136e6b51870 100644
--- a/src/_secureaccesstokenauthorizer/tests/test_plugin.py
+++ b/src/_secureaccesstokenauthorizer/tests/test_plugin.py
@@ -94,7 +94,10 @@ class PluginTests(TestCase):
         """
         ``storage_server`` provides ``IFoolscapStoragePlugin``.
         """
-        verifyObject(IFoolscapStoragePlugin, storage_server)
+        self.assertThat(
+            storage_server,
+            Provides([IFoolscapStoragePlugin]),
+        )