diff --git a/tox.ini b/tox.ini
--- a/tox.ini
+++ b/tox.ini
@@ -8,25 +8,21 @@
   db: .[db]
   db: pifpaf
   server: .[http]
+  cover: pytest-cov
 commands =
   db: pifpaf run postgresql -- \
     pytest --doctest-modules \
+  slow: --hypothesis-profile=slow \
+  cover: --cov={envsitepackagesdir}/swh/core --cov-branch \
   core: {envsitepackagesdir}/swh/core/tests \
   db: {envsitepackagesdir}/swh/core/db/tests \
   server: {envsitepackagesdir}/swh/core/api/tests \
     {posargs}
 
 [testenv:py3]
-deps =
-  .[testing]
-  pytest-cov
-  pifpaf
-commands =
-  pifpaf run postgresql -- \
-    pytest --doctest-modules \
-	       --hypothesis-profile=slow \
-	       --cov={envsitepackagesdir}/swh/core --cov-branch \
-		   {envsitepackagesdir}/swh/core {posargs}
+skip_install = true
+deps = tox
+commands = tox -e py3-core-db-server-slow-cover -- {posargs}
 
 [testenv:flake8]
 skip_install = true