diff --git a/nbdev/test.py b/nbdev/test.py
index d1e508b9a..2378e5b9f 100644
--- a/nbdev/test.py
+++ b/nbdev/test.py
@@ -87,7 +87,8 @@ def nbdev_test(
     else: kw = {}
     with working_directory(get_config().nbs_path):
         results = parallel(test_nb, files, skip_flags=skip_flags, force_flags=force_flags, n_workers=n_workers,
-                           basepath=get_config().config_path, pause=pause, do_print=do_print, **kw)
+                           basepath=get_config().config_path, pause=pause, do_print=do_print,
+                           executor=False, maxtasksperchild=1, **kw)
     passed,times = zip(*results)
     if all(passed): print("Success.")
     else: 
diff --git a/nbs/api/12_test.ipynb b/nbs/api/12_test.ipynb
index 838b73908..afdd5b645 100644
--- a/nbs/api/12_test.ipynb
+++ b/nbs/api/12_test.ipynb
@@ -183,7 +183,8 @@
     "    else: kw = {}\n",
     "    with working_directory(get_config().nbs_path):\n",
     "        results = parallel(test_nb, files, skip_flags=skip_flags, force_flags=force_flags, n_workers=n_workers,\n",
-    "                           basepath=get_config().config_path, pause=pause, do_print=do_print, **kw)\n",
+    "                           basepath=get_config().config_path, pause=pause, do_print=do_print,\n",
+    "                           executor=False, maxtasksperchild=1, **kw)\n",
     "    passed,times = zip(*results)\n",
     "    if all(passed): print(\"Success.\")\n",
     "    else: \n",