diff --git a/pytest.ini b/pytest.ini
index de1ecf267..9a5807f34 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -1,3 +1,6 @@
+# This file isn't used while testing packages in tools/_release.sh so any
+# settings we want to also change there must be added to the release script
+# directly.
 [pytest]
 addopts = --numprocesses auto --pyargs
 # ResourceWarnings are ignored as errors, since they're raised at close
@@ -6,4 +9,4 @@ addopts = --numprocesses auto --pyargs
 filterwarnings =
     error
     ignore:decodestring:DeprecationWarning
-    ignore:TLS-SNI-01:DeprecationWarning
\ No newline at end of file
+    ignore:TLS-SNI-01:DeprecationWarning
diff --git a/tools/_release.sh b/tools/_release.sh
index 97e6e9c63..dd08974ae 100755
--- a/tools/_release.sh
+++ b/tools/_release.sh
@@ -169,7 +169,8 @@ pip freeze | tee $kgs
 pip install pytest
 for module in $subpkgs_modules ; do
     echo testing $module
-    pytest --pyargs $module
+    # use an empty configuration file rather than the one in the repo root
+    pytest -c <(echo '') --pyargs $module
 done
 cd ~-