I'm writing the book in Markdown format, which then gets converted to HTML. You would take those HTML files, and then convert them to an ePub/PDF/Mobi eBook using Calibre (or a similar Mac OS tool), making sure that everything works properly: meta-data, table of contents, cover, etc.
However, I'm specifically *not* looking for someone to do the job by filling each value inside the app.
Instead, I would like someone who can set the correct meta tags in the HTML so that even if the book's content changes later on, I will be able to re-run the conversion process by myself.
Also, note that you would not need to do any design or editing, this is only about converting from one format to another. please let me know which software you will use?