Elixir and Phoenix are stable and by now they're a solid choice (more than enough warranted praise on HN), but I'm still skeptical about Elm from a "platform" perspective. From what I can tell, Elm apps are a single blob of JavaScript that either loads or doesn't (e.g. you can't read the Elm site without JavaScript enabled), while the JavaScript ecosystem is moving towards server-rendering, dead code elimination, and "progressive web apps" so to speak. PureScript for example has dead code elimination—you can make a <1kb PureScript "Hello World" app.<p>I know the Elm team is capable of all of these—I just haven't heard of anything yet. While they're "nice to have" now, these features might become crucial and important.<p>Another interesting thing about Elm is its progressive removal of features (I think the infix operator was or is going to be removed soon) in order to make the language more approachable. I actually support this because if you need "true" ML/Haskell features, there's PureScript.<p>Anyway, glad to see Elixir and Elm being used productively!
Nice writeup. Elixir definitely seems like a solid language for web dev. For the frontend, I prefer Scala.js since I'm kind of a Scala fanboy, but I've heard great things about Elm.<p>One little comment. At the beginning of the post, you make it seem like the app needs to scale with the number of viewers, when in fact it doesn't. I think you should clarify this to avoid confusion.
> As a business owner/recruiter, I wanted something with a low entry barrier for my future hirings. Elm has a low entry barrier, the JS ecosystem/fatigue/mess doesn't.<p>This is nonsense. There's a much greater pool of talent familiar with javascript than Elm.<p>Using Elm might be marketable ("come work with Elm here!"), but it's a riskier bet for a developer given it's relative immaturity and adoption.
Even if you don't like JavaScript, it's really surprising to me that a CTO picks something like Elm that nobody uses and only a few know or are interested in [1].<p>I'm curious to know how the author will recruit developers, specially in France. My last company migrated all its backend in Node this year, ONLY because it was the easiest option to recruit full-stack developers. The market is completely saturated here (there are a lot more offers than developpers), you spend months to recruit a front-end developer or a full-stack developer with front-end knowledge, and I don't see how you can attract someone with Elm. Having 1 or 2 years of xp in Elm on a resume is not really usefull when all the companies use JavaScript. You don't even know if Elm will still be there in 2 years.<p>[1] <a href="http://stateofjs.com/2016/flavors" rel="nofollow">http://stateofjs.com/2016/flavors</a>
This was great to read and it inspired me to give both a try soon.<p>Question: Did the app receive millions of visitors or was it basically 1 visitor with millions of viewers via the television showing a recorded screen?<p>At first I thought Phoenix was used because of scaling reasons but now I'm not so sure.<p>Either way, nice work and thanks for the write up!
So I saw Elixir+Elm, Elixir+Elixirscript, Elixir+Scala.js here so far.<p>Chiming in with Elixir+Clojurescript. It's what I've been using for most of my projects these days and absolutely love it. Pure functional programming on both, server and client, with the server concentrating on well distributed concurrency and parallel processing with GenServers and the client on immutable front-end code while using Go-blocks for async stuff.
> Elm has a low entry barrier<p>Sorry Vincent, you lost me there. Elm is interesting for sure, but it's far from having a low entry barrier. Something has basic has having a button play a sound takes forever to figure out. You almost have to learn everything all over again.
It's a cool project and I'm glad it's working out well for you, but Elm has a serious learning curve.
<i>the guests were Nicolas Sarkozy (12 millions viewers), Arnaud Montebourg (9 millions) and lately Alain Juppé (13 millions).</i><p>I would like to see the results of the two other guests.
As a French trying Elixir these last few months (don't have much time for Elm) it's great seeing the language picking up some hype.<p>At work I don't see it happening though, we're a PHP shop now addind nodejs (to my despair) and maybe some Go. I think there is a Haskell fan and that's it.