diff --git a/cmd_gen/main.go b/cmd_gen/main.go
index 6fe8e39..65fb9c7 100644
--- a/cmd_gen/main.go
+++ b/cmd_gen/main.go
@@ -302,7 +302,7 @@ fi
 // runInParallel determines whether a particular validator and version should be run in parallel.
 func runInParallel(validatorId, version string) bool {
 	switch {
-	case validatorId == "goyang-ygot", validatorId == "pyang" && version == "head":
+	case validatorId == "pyang" && version == "head":
 		return false
 	default:
 		return true
diff --git a/cmd_gen/main_test.go b/cmd_gen/main_test.go
index 97f65a1..4fee1c2 100644
--- a/cmd_gen/main_test.go
+++ b/cmd_gen/main_test.go
@@ -215,9 +215,9 @@ function run-dir() {
   fi
 }
 go install golang.org/x/tools/cmd/goimports@latest &>> ${prefix}pass || status=1
-run-dir "acl" "openconfig-acl" testdata/acl/openconfig-acl.yang testdata/acl/openconfig-acl-evil-twin.yang
-run-dir "optical-transport" "openconfig-optical-amplifier" testdata/optical-transport/openconfig-optical-amplifier.yang
-run-dir "optical-transport" "openconfig-transport-line-protection" testdata/optical-transport/openconfig-transport-line-protection.yang
+run-dir "acl" "openconfig-acl" testdata/acl/openconfig-acl.yang testdata/acl/openconfig-acl-evil-twin.yang &
+run-dir "optical-transport" "openconfig-optical-amplifier" testdata/optical-transport/openconfig-optical-amplifier.yang &
+run-dir "optical-transport" "openconfig-transport-line-protection" testdata/optical-transport/openconfig-transport-line-protection.yang &
 wait
 `,
 	}, {