Typst( https://typst.app/)
Is good Latex alternative which should be mentioned here. Their roadmap also features html as a target.
replies(5):
Why would anyone switch from LaTeX to this other than the speed?
Surely both of these characterizations depend on the person? I can believe that integral_t^oo is idiomatic if that's what you're used to, and maybe it's easier to pick up from scratch, but, for someone long used to TeX, it just makes me wonder what other unpleasant surprises someone else will have decided are actually pleasant.