But that's not a library. It forces your whole project into a box in which it may not fit. Elm is not without problems as well, although they (him?) are working on the biggest pain-points.

> It forces your whole project into a box

Isn't that the point? Since Elm is a pure, strongly typed language, it introduces a lot of constraints. You can't mutate anything, there are no side effects (only declared effects captured by the type system), and the only architecture you can use is "The Elm Architecture". However, those restrictions will keep your code sane and the compiler almost guarantees that your code will work. It's a pretty fair trade-off if you ask me.