diff --git a/tox.ini b/tox.ini
index 7961499..a586d64 100644
--- a/tox.ini
+++ b/tox.ini
@@ -1,5 +1,5 @@
 [tox]
-envlist = py26, py27, py33, coverage
+envlist = py26, py27, py33, pypy, coverage
 
 [testenv]
 commands = python -m unittest discover tests/unit