diff --git a/requirements_dev.txt b/requirements_dev.txt
index ebdb195..78a9966 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -3,11 +3,11 @@
 flake8==3.7.7
 mock==2.0.0
 pip==19.0.3
-pytest==4.3.1
+pytest==4.4.0
 pytest-runner==4.4
 six==1.12.0
-Sphinx==1.8.5
-tox==3.7.0
+Sphinx==1.8.5 # pyup: <2.0 # for Python 2.7 and 3.4 support
+tox==3.8.4
 twine==1.13.0
 watchdog==0.9.0
 wheel==0.33.1