diff --git a/requirements-test.txt b/requirements-test.txt
--- a/requirements-test.txt
+++ b/requirements-test.txt
@@ -1,4 +1,5 @@
 hypothesis
-pytest
+# pytest<4 because of https://github.com/pytest-dev/pytest/issues/4641
+pytest < 4
 pytest-postgresql
 celery >= 4