diff --git a/templates/shinyproxy-2-conf.yml.j2 b/templates/shinyproxy-2-conf.yml.j2
index f5d3383..00702bc 100644
--- a/templates/shinyproxy-2-conf.yml.j2
+++ b/templates/shinyproxy-2-conf.yml.j2
@@ -128,7 +128,7 @@ proxy:
   {% endif %}
   {% if app.groups is defined %}
 
-    groups: {{ app.groups }}
+    groups: [{{ app.groups }}]
   
   {% endif %}