diff --git a/tox.ini b/tox.ini
index e0872a7b..d71c142a 100644
--- a/tox.ini
+++ b/tox.ini
@@ -45,7 +45,7 @@ commands = ./demo.py
 [testenv:mypy-modules]
 whitelist_externals = bash
 commands =
-    pip install -e .[testing] .[optional]
+    pip install -e .[testing,optional]
     pip install orgparse
     pip install git+https://github.com/karlicoss/endoexport
     pip install git+https://github.com/karlicoss/ghexport
@@ -86,5 +86,5 @@ commands =
 [testenv:mypy]
 skip_install = true
 commands =
-    pip install -e .[testing] .[optional] orgparse
+    pip install -e .[testing,optional] orgparse
     ./lint