diff --git a/tests/test_harness.py b/tests/test_harness.py
index c75dc4e..9b8876e 100644
--- a/tests/test_harness.py
+++ b/tests/test_harness.py
@@ -13,6 +13,7 @@
 TEST_DATA_DIR = Path(__file__).resolve().parent / "test_data"
 default_config = {
     "name": "DefaultHarness",
+    "mode": "actor",
     "compilationPath": ".",
     "targets": [],
     "outputDir": "./test/fuzzing",