diff --git a/tests/mailu/ops.py b/tests/mailu/ops.py
index 02e522d..f93ab08 100644
--- a/tests/mailu/ops.py
+++ b/tests/mailu/ops.py
@@ -9,7 +9,7 @@ import sys
 sys.path.insert(0, os.path.join(os.path.dirname(__file__), "..", "..", "runner"))
 from harness import lifecycle  # noqa: E402
 
-sys.path.insert(0, os.path.dirname(__file__))
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), "functional"))
 import _mailu  # noqa: E402
 
 _CI_LOCALPART = "citest"
diff --git a/tests/mailu/test_backup.py b/tests/mailu/test_backup.py
index db9be5a..2f2a7e3 100644
--- a/tests/mailu/test_backup.py
+++ b/tests/mailu/test_backup.py
@@ -9,7 +9,7 @@ from __future__ import annotations
 import os
 import sys
 
-sys.path.insert(0, os.path.dirname(__file__))
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), "functional"))
 import _mailu  # noqa: E402
 
 _CI_LOCALPART = "citest"
diff --git a/tests/mailu/test_restore.py b/tests/mailu/test_restore.py
index 3c3695e..1dd6cdf 100644
--- a/tests/mailu/test_restore.py
+++ b/tests/mailu/test_restore.py
@@ -9,7 +9,7 @@ from __future__ import annotations
 import os
 import sys
 
-sys.path.insert(0, os.path.dirname(__file__))
+sys.path.insert(0, os.path.join(os.path.dirname(__file__), "functional"))
 import _mailu  # noqa: E402
 
 _CI_LOCALPART = "citest"