diff --git a/pytest.ini b/pytest.ini
index 59b6e648390e942bcf0f595fecf7d4541019976b..7a65a5085096bdea5ae8a8e66f58dd401e93d18e 100644
--- a/pytest.ini
+++ b/pytest.ini
@@ -2,3 +2,5 @@
 norecursedirs = build docs .*
 markers =
     graph: execute tests that depend on swh-graph
+
+asyncio_mode = strict