diff --git a/requirements-test.txt b/requirements-test.txt
--- a/requirements-test.txt
+++ b/requirements-test.txt
@@ -1,9 +1,10 @@
-pytest
+attrs
 dulwich >= 0.18.7
+pytest
+pytest-mock
 swh.loader.core
 swh.loader.git >= 0.8
 swh.storage[testing]
-pytest-mock
 types-click
 types-python-dateutil
 types-pyyaml
diff --git a/swh/vault/tests/test_cookers.py b/swh/vault/tests/test_cookers.py
--- a/swh/vault/tests/test_cookers.py
+++ b/swh/vault/tests/test_cookers.py
@@ -17,7 +17,7 @@
 import unittest
 import unittest.mock
 
-import attrs
+import attr
 import dulwich.fastexport
 import dulwich.index
 import dulwich.objects
@@ -442,7 +442,7 @@
         # alter the content of the storage
         # 1/ make file 2 an hidden file object
         loader.storage._allow_overwrite = True
-        cnt2 = attrs.evolve(
+        cnt2 = attr.evolve(
             loader.storage.content_get([id_2])[0], status="hidden", data=file_2
         )
         loader.storage.content_add([cnt2])
@@ -826,7 +826,7 @@
         # alter the content of the storage
         # 1/ make file 2 an hidden file object
         loader.storage._allow_overwrite = True
-        cnt2 = attrs.evolve(
+        cnt2 = attr.evolve(
             loader.storage.content_get([id_2])[0], status="hidden", data=file_2
         )
         loader.storage.content_add([cnt2])