diff --git a/tests/test_newpolygons.py b/tests/test_newpolygons.py
index 18d7faacd..6eb431727 100644
--- a/tests/test_newpolygons.py
+++ b/tests/test_newpolygons.py
@@ -380,7 +380,7 @@ def test_ketos_new_arrow(self):
             mfp2 = str(Path(tempdir) / "model2")
 
             self._test_ketoscli(
-                args=['compile', '-f', 'xml', '-o', dset, self.segmented_img],
+                args=['compile', '--workers', '0', '-f', 'xml', '-o', dset, self.segmented_img],
                 expect_legacy=False,
                 patching_dir="kraken.lib.arrow_dataset",
             )
@@ -399,7 +399,7 @@ def test_ketos_new_arrow_force_legacy(self):
             mfp2 = str(Path(tempdir) / "model2")
 
             self._test_ketoscli(
-                args=['compile', '--legacy-polygons', '-f', 'xml', '-o', dset, self.segmented_img],
+                args=['compile', '--workers', '0', '--legacy-polygons', '-f', 'xml', '-o', dset, self.segmented_img],
                 expect_legacy=True,
                 patching_dir="kraken.lib.arrow_dataset",
             )
@@ -428,7 +428,7 @@ def test_ketos_new_arrow_old_model(self):
             mfp2 = str(Path(tempdir) / "model2")
 
             self._test_ketoscli(
-                args=['compile', '-f', 'xml', '-o', dset, self.segmented_img],
+                args=['compile', '--workers', '0', '-f', 'xml', '-o', dset, self.segmented_img],
                 expect_legacy=False,
                 patching_dir="kraken.lib.arrow_dataset",
             )
@@ -445,7 +445,7 @@ def test_ketos_mixed_arrow_train_new(self):
             mfp = str(Path(tempdir) / "model")
 
             self._test_ketoscli(
-                args=['compile', '-f', 'xml', '-o', dset, self.segmented_img, self.arrow_data],
+                args=['compile', '--workers', '0', '-f', 'xml', '-o', dset, self.segmented_img, self.arrow_data],
                 expect_legacy=False,
                 patching_dir="kraken.lib.arrow_dataset",
             )