So elm is a strongly typed functional programming language, loosely related to Haskell, it contains a MVC system thats message driven, and it seems like its a pretty pleasant experience for working in the browser.
to install elm you just have to do this
npm install -g elm elm-test elm-format elm-analyse
VS code support for it seems to be pretty solid.
To startup the reactor and run the code all you need to do is ask for elm reactor
elm reactor