Support for macros in adf builder

Hello team
Is there any support in adf builder to display macros?
However upon seeing one of the old adf templates in atlassian codebase i see

<@heading header='Timeline' level=4/>,
  "type": "paragraph",
  "content": [
        "text":" | incidentId = ${postmortem.incidentId}",

which is used to render a macro
I however don’t see api documentation in Document builder