diff --git a/lib/cartodb/controllers/layergroup.js b/lib/cartodb/controllers/layergroup.js
index 1a853bd9..7010afa6 100644
--- a/lib/cartodb/controllers/layergroup.js
+++ b/lib/cartodb/controllers/layergroup.js
@@ -87,7 +87,7 @@ LayergroupController.prototype.register = function(app) {
         `${basePath}/:token/:layer/:z/:x/:y.(:format)`,
         cors(),
         userMiddleware,
-        validateLayerRouteMiddleware,
+        validateLayerRoute(),
         this.prepareContext,
         this.getMapStoreMapConfigProvider(this.mapStore, this.userLimitsApi),
         this.layer(this.tileBackend),
@@ -244,12 +244,14 @@ LayergroupController.prototype.register = function(app) {
     );
 };
 
-function validateLayerRouteMiddleware(req, res, next) {
-    if (req.params.token === 'static') {
-        return next('route');
-    }
+function validateLayerRoute () {
+    return function validateLayerRouteMiddleware(req, res, next) {
+        if (req.params.token === 'static') {
+            return next('route');
+        }
 
-    next();
+        next();
+    };
 }
 
 LayergroupController.prototype.analysisNodeStatus = function (analysisStatusBackend) {