diff --git a/tox.ini b/tox.ini
index 1ce5b7b..d64e40c 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,7 +1,8 @@
 [tox]
-minversion = 1.8
+minversion = 3.1.0
 skipsdist = True
 envlist = py3,pep8
+ignore_basepython_conflict=true
 
 [testenv]
 basepython = python3