(Demo) http://dreamwriter.io is something I built in my free time.

This is something I originally made a few years ago, to scratch my own itch. I like to write novels, and I found Google Docs lacking. There were some extra features I wanted, like a first-class notion of chapters, a word count that updates as I write, a fullscreen "distraction-free" mode, etc.

I made a prototype, iterated a few times, and finally arrived at a design I liked...with a totally unmaintainable code base. I knew I'd have to rewrite it sooner or later.

I was partway through rewriting it with CoffeeScript, React, and Flux, when this blog post came out: http://elm-lang.org/blog/Blazing-Fast-Html.elm

Those benchmarks really caught my eye, because performance was so important to me on Dreamwriter. So I started poking around, and reading about it, and it turned out that it had an architecture similar to React and Flux, with immutability...except the whole language was built around it!

Then I came across this demo of the time-traveling debugger: http://debug.elm-lang.org/edit/Mario.elm

This is crazy! It's stuff I remember seeing Bret Victor talking about, saying someday in the future these are the kinds of tools we should have as developers...and it's already here?