My first reaction was that "this sucks, who would want to use some non-established DSL over universally understood JavaScript". But thinking about it more, this is just like functional CSS libraries (e.g. Tailwind CSS) that allow you to compose behavior from strings that you bake into the HTML. I don't agree with the syntax here or the use of `_` instead `data-*`, but I think it's worth looking into encoding common UI behavior into HTML classes or a custom data-* attribute.