Building Loris' supermd

I am installing the language support in helix for the formats used by Loris’ zine , following this link.
At the end it indicates to get all the commandline tools. ziggy and superhtml were no problem as these are available as releases (and superhtml also builds from the cloned repo).
But there is no releases for supermd and zig build in the clone of the repo builds an executable docgen which is not the correct executable.
How can I get a working supermd executable?

Could be wrong, but it doesn’t seem like there’s anything you need to build for supermd, there’s just some syntax highlighting stuff in editors/helix/queries

You may be right. On closer inspection there is no language-server entry for supermd, although there is for the other two. And there are grammars, but those might not be for an LSP server.
I think I had expected a commandline utility that could convert .smd to .shtml