diff --git a/stack.sh b/stack.sh
index 5ba60d2..c9d394c 100755
--- a/stack.sh
+++ b/stack.sh
@@ -647,7 +647,7 @@
 # Install python packages into a virtualenv so that we can track them
 if [[ $TRACK_DEPENDS = True ]]; then
     echo_summary "Installing Python packages into a virtualenv $DEST/.venv"
-    install_package python-virtualenv
+    pip_install -U virtualenv
 
     rm -rf $DEST/.venv
     virtualenv --system-site-packages $DEST/.venv