diff --git a/tox.ini b/tox.ini
index bcacef3..1761a8f 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,12 +4,12 @@ minversion = 3.5
 # hack to prevent .tox from crapping to the project directory
 toxworkdir={env:TOXWORKDIR_BASE:}{toxinidir}/.tox
 
-# useful for tests to know they are running under ci
-# respect user's cache dirs to prevent tox from crapping into project dir
 [testenv]
 passenv =
+    # useful for tests to know they are running under ci
     CI
     CI_*
+    # respect user's cache dirs to prevent tox from crapping into project dir
     MYPY_CACHE_DIR
     PYTHONPYCACHEPREFIX