diff --git a/.config/kak/autoload/filetype/mermaid.kak b/.config/kak/autoload/filetype/mermaid.kak
index 5c37a363..2c300775 100644
--- a/.config/kak/autoload/filetype/mermaid.kak
+++ b/.config/kak/autoload/filetype/mermaid.kak
@@ -4,14 +4,25 @@ hook global BufCreate .+[.](mmd|mermaid) %{
 
 hook global WinSetOption filetype=mermaid %{
     require-module mermaid
+
+    hook window InsertChar \n -group mermaid-indent mermaid-indent-on-new-line
+    hook window ModeChange pop:insert:.* -group mermaid-trim-indent mermaid-trim-indent
+
+    hook -once -always window WinSetOption filetype=.* %{ remove-hooks window mermaid-.+ }
+    
     set-option window indentwidth 2
     set-option window comment_line '%%'
 }
 
 provide-module mermaid %—
+    # TODO: regex highlighting (treesitter is overkill lol)
     define-command -hidden mermaid-indent-on-new-line %~
         # preserve prev line indent
         try %{ execute-keys -draft <semicolon> K <a-&> }
     ~
 
+    define-command -hidden mermaid-trim-indent %{
+        # rm trailing whitespace
+        try %{ execute-keys -draft -itersel x s \h+$ <ret> d }
+    }
 —