I’m a huge fan of CoffeeScript and use it wherever I can... It works for the most part but I had to straddle the syntactical line between brittle and overwrought, with all of the extra brackets.

I don't know what extra brackets are referred to here without code samples, but based on the link to Vjeux's post [0], they are completely unnecessary, given the behavior of React vis-a-vis multiple parameters and CoffeeScript with syntactic whitespace and object literals, at least as of CoffeeScript 1.7... For instance, the example:

    {div, h3, textarea} = React.DOM
    (div {className: 'MarkdownEditor'}, [
      (h3 {}, 'Input'),
      (textarea {onKeyUp: @handleKeyUp, ref: 'textarea'},
        @state.value
      )
    ])

Could be written with far less punctuation as:

    {div, h3, textarea} = React.DOM
    div
      className: 'MarkdownEditor'
      h3 {}, 'Input'
      textarea
        onKeyUp: @handleKeyUp
        ref: 'textarea'
        @state.value

(Though I usually pass null as the empty param to make it feel worse...)

[0]: http://blog.vjeux.com/2013/javascript/react-coffeescript.htm...