diff --git a/requirements_dev.txt b/requirements_dev.txt
index 069cad0..cfcae85 100644
--- a/requirements_dev.txt
+++ b/requirements_dev.txt
@@ -1,12 +1,12 @@
-pip==10.0.1
+pip==18.0
 bumpversion==0.5.3
 wheel==0.31.1
 watchdog==0.8.3
 flake8==3.5.0
-tox==3.0.0
+tox==3.1.3
 coverage==4.5.1
-Sphinx==1.7.5
-cryptography==2.2.2
-PyYAML==3.12
+Sphinx==1.7.6
+cryptography==2.3
+PyYAML==3.13
 twine==1.11.0