diff --git a/tests/fixtures/dzg.versions b/tests/fixtures/dzg.versions
new file mode 100644
index 0000000..6ebdc35
--- /dev/null
+++ b/tests/fixtures/dzg.versions
@@ -0,0 +1,8 @@
+1559212036,1771519119
+1564026768,1770917948
+2545327648,1780174455
+2276010135,1756744083
+1654462998,1780501511
+3410710885,1752864732
+2918418331,1780413260
+3739934289,1780855136
diff --git a/tests/test_mod_signatures.py b/tests/test_mod_signatures.py
new file mode 100644
index 0000000..8aa5dd6
--- /dev/null
+++ b/tests/test_mod_signatures.py
@@ -0,0 +1,52 @@
+import pytest
+import shutil
+import tempfile
+
+from pathlib import Path
+from typing import TYPE_CHECKING
+
+import dzgui.api.mods
+import dzgui.config.query
+
+from tests.fixtures import fixture_path
+
+if TYPE_CHECKING:
+    from dzgui.const.enums import Preferences
+
+pytestmark = pytest.mark.mods
+
+@pytest.fixture
+def versions() -> str:
+    return fixture_path("dzg.versions")
+
+@pytest.fixture
+def tmp() -> str:
+    with tempfile.NamedTemporaryFile(delete=False) as f:
+        tmp = f.name
+    return tmp
+
+def mock_local_ids(path: Path) -> list[int]:
+    return [3410710885, 3739934289]
+
+def mock_lookup(path: Path, prefs: "Preferences") -> str:
+    return ""
+
+def test_signatures(monkeypatch, tmp: str, versions: str) -> None:
+    ids = [1559212036, 1654462998]
+    shutil.copyfile(versions, tmp)
+    path = Path(tmp)
+    monkeypatch.setattr("dzgui.api.mods.lookup", mock_lookup)
+    dzgui.api.mods.remove_stale_signatures(path, path, ids)
+    with open(tmp, "r") as f:
+        lines = f.readlines()
+    assert ids not in lines
+
+def test_signatures_with_no_ids(monkeypatch, tmp: str, versions: str) -> None:
+    shutil.copyfile(versions, tmp)
+    path = Path(tmp)
+    monkeypatch.setattr("dzgui.api.mods.get_local_mod_ids", mock_local_ids)
+    monkeypatch.setattr("dzgui.api.mods.lookup", mock_lookup)
+    dzgui.api.mods.remove_stale_signatures(path, path)
+    with open(tmp, "r") as f:
+        lines = f.readlines()
+    assert lines == ["3410710885,1752864732\n", "3739934289,1780855136\n"]