diff --git a/conftest.py b/conftest.py
new file mode 100644
--- /dev/null
+++ b/conftest.py
@@ -0,0 +1 @@
+pytest_plugins = ["swh.storage.pytest_plugin"]
diff --git a/swh/loader/mercurial/tests/conftest.py b/swh/loader/mercurial/tests/conftest.py
--- a/swh/loader/mercurial/tests/conftest.py
+++ b/swh/loader/mercurial/tests/conftest.py
@@ -11,7 +11,6 @@
 from typing import Any, Dict
 
 from swh.scheduler.tests.conftest import *  # noqa
-from swh.storage.tests.conftest import *  # noqa
 
 
 @pytest.fixture
diff --git a/tox.ini b/tox.ini
--- a/tox.ini
+++ b/tox.ini
@@ -6,7 +6,6 @@
   testing
 deps =
   pytest-cov
-  swh.storage[testing]
 commands =
   pytest --cov={envsitepackagesdir}/swh/loader/mercurial \
          {envsitepackagesdir}/swh/loader/mercurial \