diff --git a/runtime/ftplugin/yaml.vim b/runtime/ftplugin/yaml.vim
index db7cbd7..8bfc45e 100644
--- a/runtime/ftplugin/yaml.vim
+++ b/runtime/ftplugin/yaml.vim
@@ -16,6 +16,13 @@
 setlocal comments=:# commentstring=#\ %s expandtab
 setlocal formatoptions-=t formatoptions+=croql
 
+" rime input method engine uses `*.custom.yaml` as its config files
+if expand('%:r:e') ==# 'custom'
+  compiler rime_deployer
+  setlocal include=__include:\\s*
+  let b:undo_ftplugin ..= " inc<"
+endif
+
 if !exists("g:yaml_recommended_style") || g:yaml_recommended_style != 0
   let b:undo_ftplugin ..= " sw< sts<"
   setlocal shiftwidth=2 softtabstop=2