diff --git a/config/routes.rb b/config/routes.rb
index 8b77b6fc916..f324bca3ae3 100644
--- a/config/routes.rb
+++ b/config/routes.rb
@@ -7,9 +7,9 @@ require_dependency "permalink_constraint"
 
 # This used to be User#username_format, but that causes a preload of the User object
 # and makes Guard not work properly.
-USERNAME_ROUTE_FORMAT = /[A-Za-z0-9\_.\-]+/ unless defined? USERNAME_ROUTE_FORMAT
+USERNAME_ROUTE_FORMAT = /[\w.\-]+/ unless defined? USERNAME_ROUTE_FORMAT
 
-BACKUP_ROUTE_FORMAT = /[a-zA-Z0-9\-_]*\d{4}(-\d{2}){2}-\d{6}\.(tar\.gz|t?gz)/i unless defined? BACKUP_ROUTE_FORMAT
+BACKUP_ROUTE_FORMAT = /[\w.\-]+\.(tar\.gz|tgz)/i unless defined? BACKUP_ROUTE_FORMAT
 
 Discourse::Application.routes.draw do