diff --git a/shiny-k8s-toolkit-helm/templates/deployment.yaml b/shiny-k8s-toolkit-helm/templates/deployment.yaml
index 989e58afbb6c9bf1b8f9dd67967b0a00e7cbf108..9df703a4d88ffefdccfd8b26e9fc1f674e945513 100644
--- a/shiny-k8s-toolkit-helm/templates/deployment.yaml
+++ b/shiny-k8s-toolkit-helm/templates/deployment.yaml
@@ -41,6 +41,7 @@ spec:
           securityContext:
             runAsGroup: 999
             runAsUser: 999
+            readOnlyRootFilesystem: true
           ports:
             - name: http
               containerPort: 3838