--- a/modules/funsize_scheduler/manifests/init.pp
+++ b/modules/funsize_scheduler/manifests/init.pp
@@ -46,15 +46,15 @@ class funsize_scheduler {
                 "pycrypto==2.6.1",
                 "python-jose==0.5.2",
                 "redo==1.4.1",
                 # Taskcluster pins requests 2.4.3, so we need to de the same,
                 # even though we'd rather use a more up-to-date version.
                 "requests[security]==2.4.3",
                 "setuptools==33.1.1",
                 "singledispatch==3.4.0.3",
-                "six==1.9.0",
+                "six==1.10.0",
                 "slugid==1.0.6",
                 "taskcluster>=0.0.26",
                 "wsgiref==0.1.2",
             ];
     }
 }