On: ExactTex. A gradually-typed superset of LaTeX

[fph]

But one of its problems surely is "horrible error messages", and this project addresses it, too.

[xigoi → fph]

However, it doesn’t address the atrocious compile times, excessively verbose syntax and fragile macro system.

[camilochs → xigoi]

The thing is, my goal was to enhance the text editor and improve the error messages, but not to abandon TeX. That's the price I have to pay.