diff --git a/lib/models/post.js b/lib/models/post.js
index <HASH>..<HASH> 100644
--- a/lib/models/post.js
+++ b/lib/models/post.js
@@ -55,9 +55,9 @@ module.exports = function(ctx) {
   });
 
   Post.virtual('permalink').get(function() {
-    var url_for = ctx.extend.helper.get('url_for');
+    var self = _.assign({}, ctx.extend.helper.list(), ctx);
     var config = ctx.config;
-    var partial_url = url_for.call(ctx, this.path);
+    var partial_url = self.url_for(this.path);
     return config.url + _.replace(partial_url, config.root, '/');
   });
Update post.js (#<I>)