diff --git a/tox.ini b/tox.ini
--- a/tox.ini
+++ b/tox.ini
@@ -7,7 +7,9 @@
 deps =
   pytest-cov
   dev: pdbpp
+allowlist_externals = docker
 commands =
+  docker run debian:bullseye date
   pytest --cov={envsitepackagesdir}/swh/objstorage \
          {envsitepackagesdir}/swh/objstorage \
          --cov-branch {posargs}