diff --git a/roles/simple-reverse-proxy/templates/nginx-configuration.conf.j2 b/roles/simple-reverse-proxy/templates/nginx-configuration.conf.j2
index 7b1ca6f..4d0631f 100644
--- a/roles/simple-reverse-proxy/templates/nginx-configuration.conf.j2
+++ b/roles/simple-reverse-proxy/templates/nginx-configuration.conf.j2
@@ -1,6 +1,6 @@
 server {
-  listen 443 ssl;
-  listen [::]:443 ssl;
+  listen {{ simple_reverse_proxy_external_port }} ssl;
+  listen [::]:{{ simple_reverse_proxy_external_port }} ssl;
   server_name {{ simple_reverse_proxy_internal_subdomain }}.kleinendorst.info;
 
   client_max_body_size 20M;
diff --git a/roles/simple-reverse-proxy/vars/main/defaults.yml b/roles/simple-reverse-proxy/vars/main/defaults.yml
new file mode 100644
index 0000000..ad60add
--- /dev/null
+++ b/roles/simple-reverse-proxy/vars/main/defaults.yml
@@ -0,0 +1,2 @@
+---
+simple_reverse_proxy_external_port: 443