diff --git a/tox.ini b/tox.ini
--- a/tox.ini
+++ b/tox.ini
@@ -1,9 +1,10 @@
 [tox]
 envlist=flake8,mypy,py3
 
-[testenv:py3]
+[testenv]
+extras =
+  testing
 deps =
-  .[testing]
   pytest-cov
 whitelist_externals =
   mvn
@@ -22,9 +23,9 @@
   {envpython} -m flake8
 
 [testenv:mypy]
-skip_install = true
+extras =
+  testing
 deps =
-  .[testing]
   mypy
 commands =
   mypy swh