diff --git a/tox.ini b/tox.ini
index c3ef0b2c..bd763c52 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,11 +1,12 @@
 [tox]
 envlist = py34,py35
 skipsdist = True
+skip_missing_interpreters = True
 
 [testenv]
 commands =
     flake8
-    py.test core core_se core_me core_pe hscommon
+    py.test core hscommon
 deps =
     -r{toxinidir}/requirements.txt
     -r{toxinidir}/requirements-extra.txt