I have used markdown with custom lua filters for things like chapter delimiters, non breaking spaces and notes for inserting images. But my setup was kinda wonk

I have used markdown with custom lua filters for things like chapter delimiters, non breaking spaces and notes for inserting images. But my setup was kinda wonky as I exported from markdown to ODT and then used LibreOffice to convert it to PDF while adding images to the layout manually as this is impossible to mechanize with LibreOffice.