diff --git a/dev/release.sh b/dev/release.sh
index 1c7cfb04..77dcf866 100755
--- a/dev/release.sh
+++ b/dev/release.sh
@@ -8,6 +8,8 @@ CHANGES="/tmp/vulture-$VERSION-changes"
 cd "$(dirname ${0})/../"
 
 # Check dependencies.
+hub --version > /dev/null
+tox --version > /dev/null
 twine -h > /dev/null
 
 # Check for uncommitted changes.