Elm was the inspiration behind Redux which is currently sweeping through the JavaScript UI community.

Elm is typed and succinct and it has a lot of expressive power as a functional language (more similar in style to Haskell than JavaScript). I don’t claim to have mastered it but I will say that the Elm approach has been well and truly vindicated through thousands of Redux, RxJs/store and Vuex implementations which all refer back to Elm. Once you strip out all the ceremony and boilerplate from Javascript frameworks (yes, I’m looking at you Angular2) there’s not much left that can’t be more compactly expressed in Elm.

My only quibble with the language, apart from the unfamiliarity of the syntax is the not very simple way it interacts with Javascript libraries. This is by necessity but it means there’s a bit more work bridging the gap.

https://css-tricks.com/introduction-elm-architecture-build-first-application/

https://auth0.com/blog/web-components-how-to-craft-your-own-custom-components/