diff --git a/dev-requirements.txt b/dev-requirements.txt
--- a/dev-requirements.txt
+++ b/dev-requirements.txt
@@ -14,6 +14,6 @@ jinja2==2.8               # via flask, s
 markupsafe==0.23          # via jinja2
 pip-tools==1.1.3
 pygments==2.0.2           # via sphinx
-six==1.9.0                # via pip-tools
+six==1.10.0               # via pip-tools
 Sphinx==1.2.3
 werkzeug==0.10.4          # via flask