diff --git a/src/lua/runtime/h.lua b/src/lua/runtime/h.lua
index 7b7acae..7e25f3a 100644
--- a/src/lua/runtime/h.lua
+++ b/src/lua/runtime/h.lua
@@ -3,6 +3,9 @@
 local h = {}
 
 h.document = maivi.elem("!DOCTYPE html", { close = false })
+h.comment = function(str)
+  return string.format("<!-- %s -->", str)
+end
 
 -- void elements
 -- https://developer.mozilla.org/en-US/docs/Glossary/Void_element