diff --git a/tox.ini b/tox.ini
index 9407b70d6517..2193faf4af15 100644
--- a/tox.ini
+++ b/tox.ini
@@ -8,9 +8,13 @@ envlist = py35, py36
 
 [testenv]
 changedir = /tmp
+setenv =
+    MPLCONFIGDIR={envtmpdir}/.matplotlib
+    PIP_USER = 0
+    PIP_ISOLATED = 1
+    MPLLOCALFREETYPE = 1
+usedevelop = True
 commands =
-    sh -c 'rm -f $HOME/.matplotlib/fontList*'
-    {envpython} {toxinidir}/tests.py --processes=-1 --process-timeout=300
+    pytest --pyargs matplotlib
 deps =
-    numpy
     pytest