diff --git a/ssl/test/bssl_shim.cc b/ssl/test/bssl_shim.cc
index 571680b..c0d5475 100644
--- a/ssl/test/bssl_shim.cc
+++ b/ssl/test/bssl_shim.cc
@@ -205,6 +205,7 @@
   }
   memcpy(out, bssl::vector_data(&test_state->signature),
          test_state->signature.size());
+  *out_len = test_state->signature.size();
 
   test_state->signature.clear();
   test_state->signature_retries = 0;
diff --git a/ssl/test/runner/runner.go b/ssl/test/runner/runner.go
index d66dc74..35d0bc6 100644
--- a/ssl/test/runner/runner.go
+++ b/ssl/test/runner/runner.go
@@ -2234,6 +2234,24 @@
 				"-use-async-private-key",
 			},
 		})
+		tests = append(tests, testCase{
+			testType: serverTest,
+			name:     "Basic-Server-RSAAsyncKey",
+			flags: []string{
+				"-cert-file", path.Join(*resourceDir, rsaCertificateFile),
+				"-key-file", path.Join(*resourceDir, rsaKeyFile),
+				"-use-async-private-key",
+			},
+		})
+		tests = append(tests, testCase{
+			testType: serverTest,
+			name:     "Basic-Server-ECDSAAsyncKey",
+			flags: []string{
+				"-cert-file", path.Join(*resourceDir, ecdsaCertificateFile),
+				"-key-file", path.Join(*resourceDir, ecdsaKeyFile),
+				"-use-async-private-key",
+			},
+		})
 	}
 	tests = append(tests, testCase{
 		testType: serverTest,