--- settings.js
+++ settings.js
@@ -245,6 +245,7 @@ const settings = {
   // address and http/https protocol information.

   behindProxy: process.env.SHARELATEX_BEHIND_PROXY || false,
+  trustedProxyIps: process.env.SHARELATEX_TRUSTED_PROXY_IPS,

   i18n: {
     subdomainLang: {
