diff -upr a/cheroot/test/test_ssl.py b/cheroot/test/test_ssl.py
--- a/cheroot/test/test_ssl.py	2020-07-13 16:43:42.000000000 +0200
+++ b/cheroot/test/test_ssl.py	2020-07-13 18:53:44.015966639 +0200
@@ -212,7 +212,6 @@ def test_ssl_adapters(
 @pytest.mark.parametrize(
     'adapter_type',
     (
-        'builtin',
         'pyopenssl',
     ),
 )
