diff --git a/runtime/autoload/dist/ft.vim b/runtime/autoload/dist/ft.vim
index ff554df..4c2d20a 100644
--- a/runtime/autoload/dist/ft.vim
+++ b/runtime/autoload/dist/ft.vim
@@ -819,7 +819,9 @@
 enddef
 
 export def FTsys()
-  if IsRapid()
+  if exists("g:filetype_sys")
+    exe "setf " .. g:filetype_sys
+  elseif IsRapid()
     setf rapid
   else
     setf bat