diff --git a/roles/wsgi_website/templates/nginx_site.j2 b/roles/wsgi_website/templates/nginx_site.j2
index cd5865d0d0893023b31c51289e4a59f2ab173c31..361af0e1a948200036a994b49f3f290c9622134f 100644
--- a/roles/wsgi_website/templates/nginx_site.j2
+++ b/roles/wsgi_website/templates/nginx_site.j2
@@ -59,7 +59,7 @@ server {
         proxy_set_header Host $http_host;
         proxy_redirect off;
 
-    {% for header, value in proxy_headers.items() -%}
+    {% for header, value in proxy_headers | dictsort -%}
     proxy_set_header {{ header }} {{ value }};
     {% endfor -%}