Laudable, but I don't think TapirMD will gain much traction.
First, your landing page doesn't describe how TapirMD fits into the Markdown universe. I just see a list of features. Why should I read the list? Ah, the spec page[0] has some info, but it should really be on the landing page.
Second, and more importantly, TapirMD is not a superset of CommonMark[1]. GitHub had its own flavor of MD, but it's been some years now since they migrated to a CommonMark base plus extensions[2].
I recommend looking more closely at the CommonMark universe and innovating there.
I’m delighted to see this project evolving and look forward to following its development! I’ve used just about every markup technology over my (many) years as a tech writer, from troff macros, to SGML/DocBook and then XML/DITA, and finally, to Markup with the Material for MkDocs project, as a sponsor. Each has its strengths and weaknesses, but for enabling contributors outside the tech writing community, simpler source formats are the way.
That said, if pressed, I’d recommend AsciiDoc[0] over any Markup flavor for a greenfield project _today_. We had to either add or bake plugins or extensions to get features that are already included in AsciiDoc, making our Markup implementation both more complex and wholly unique. That wasn’t a huge problem, because we didn’t have a large pool of contributors to educate and support, but it would have been much easier just to point to a standard.
But, hey! The roadmap includes modules, to make way for other source formats! This is the way. :-)
First, your landing page doesn't describe how TapirMD fits into the Markdown universe. I just see a list of features. Why should I read the list? Ah, the spec page[0] has some info, but it should really be on the landing page.
Second, and more importantly, TapirMD is not a superset of CommonMark[1]. GitHub had its own flavor of MD, but it's been some years now since they migrated to a CommonMark base plus extensions[2].
I recommend looking more closely at the CommonMark universe and innovating there.
[0] https://tmd.tapirgames.com/specification.html [1] https://commonmark.org/ [2] https://github.github.com/gfm/