diff --git a/pyproject.toml b/pyproject.toml
index 60fbff9378d..bee8b0481f3 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -116,6 +116,7 @@ module = [
   "nc_time_axis.*",
   "netCDF4.*",
   "netcdftime.*",
+  "numcodecs.*",
   "opt_einsum.*",
   "pint.*",
   "pooch.*",
diff --git a/xarray/tests/test_backends.py b/xarray/tests/test_backends.py
index 7bd1f60535b..70b586882c5 100644
--- a/xarray/tests/test_backends.py
+++ b/xarray/tests/test_backends.py
@@ -2273,6 +2273,7 @@ def test_read_non_consolidated_warning(self) -> None:
                     assert_identical(ds, expected)
 
     def test_non_existent_store(self) -> None:
+        exc: type[Exception]
         if have_zarr_v3:
             exc = ValueError
             msg = "store mode"