diff --git a/properties/__init__.py b/properties/__init__.py
new file mode 100644
index 00000000000..e69de29bb2d
diff --git a/pyproject.toml b/pyproject.toml
index 2ada0c1c171..4704751b445 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -87,6 +87,7 @@ exclude_lines = ["pragma: no cover", "if TYPE_CHECKING"]
 [tool.mypy]
 enable_error_code = "redundant-self"
 exclude = [
+  'build',
   'xarray/util/generate_.*\.py',
   'xarray/datatree_/doc/.*\.py',
 ]