It's good to see concrete examples of Elm and this is definitely an easily digestible (even pre-coffee) article, but I found the first five paragraphs rather hard to swallow. I get that the author has jumped on the bandwagon that JavaScript is "troublesome", mutability is bad, purity is good, etc... but just stating all those as "facts" with precious little explanation, delivered in a preachy tone ("the siren call of that feature inexorably leads to one cheating"), is really rather worthless at this point. And linking to the Wikipedia page for "fail-fast" to explain why JavaScript's apparent "swallowing of errors" is something "we know is a wrong idea in programming" - frankly that was just irritating.