diff --git a/.gitignore b/.gitignore
index 70c7520..ac2069c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -19,6 +19,7 @@ downloads/
 eggs/
 .eggs/
 lib/
+!tests/mock_device/lib/
 lib64/
 parts/
 sdist/
diff --git a/tests/mock_device/lib/adafruit_waveform/.gitkeep b/tests/mock_device/lib/adafruit_waveform/.gitkeep
new file mode 100644
index 0000000..e69de29
diff --git a/tests/test_circup.py b/tests/test_circup.py
index 0006e10..8637aae 100644
--- a/tests/test_circup.py
+++ b/tests/test_circup.py
@@ -443,7 +443,7 @@ def test_Module_update_dir():
     with mock.patch("circup.backends.shutil") as mock_shutil, mock.patch(
         "circup.logger.warning"
     ) as mock_logger:
-        backend = DiskBackend("mock_device", mock_logger)
+        backend = DiskBackend("tests/mock_device", mock_logger)
         m = Module(
             name,
             backend,