Om and Flux 12 years ago
I'm has a fantastic tutorial for new users: https://github.com/swannodette/om/wiki/Basic-Tutorial
The same author created a LightTable tutorial to introduce ClojureScript that's also pretty great: https://github.com/swannodette/lt-cljs-tutorial
I don't use LightTable regularly, but I did for these walkthroughs. I would recommend doing the same unless you have a good Vim or Emacs environment already setup.