Even as someone who knows Haskell, it isn&#x27;t actually possible to read this article and figure out what specifically about Haskell is helping.<p>My suspicion is that it is Haskell&#x27;s great support for domain-specific languages. This is both in the sense of languages that are really &quot;just&quot; Haskell APIs but work in such an different manner that they are quite different, and in the sense of writing a full compiler [1] (or any subset of a compiler) for a new language.<p>For an example of the former, one of my favorite demonstrations is the &quot;probability monad&quot;, in which one ends up with a sort of sublanguage inside of Haskell that is probability aware: <a href="http:&#x2F;&#x2F;www.randomhacks.net&#x2F;2007&#x2F;02&#x2F;22&#x2F;bayes-rule-and-drug-tests&#x2F;" rel="nofollow">http:&#x2F;&#x2F;www.randomhacks.net&#x2F;2007&#x2F;02&#x2F;22&#x2F;bayes-rule-and-drug-te...</a> [2] If you want to start to really grasp the power of Haskell, you could do worse than meditate on how you&#x27;d implement that in your $FAVORITE_LANGUAGE... and then, most likely, burst into tears when someone shows you just how much of Haskell still works, unchanged, even in that environment (e.g., everything in Control.Monad), rather than having to be implemented in a parallel type hierarchy (or, put another way, producing a new &quot;color&quot; of functions [3]).<p>While I doubt they use something exactly like that, it&#x27;s not hard to see how that sort of thing could make it fairly easy to write spam classification code with a lot of the basic plumbing abstracted away entirely.<p>There&#x27;s a lot of examples of the latter, but I&#x27;m not sure of a really solid open source example to point at. I know it&#x27;s a common move in industry, though.<p>For bonus points, these things compose together just fine; you could easily take the probability monad and build a new language on top of it.<p>[1]: And I do mean real compiler, by anybody&#x27;s definition, all the way down to assembler if you like. Haskell&#x27;s a pretty good base language for that sort thing.<p>[2]: Or see <a href="http:&#x2F;&#x2F;blog.plover.com&#x2F;prog&#x2F;haskell&#x2F;probmonad-refs.html" rel="nofollow">http:&#x2F;&#x2F;blog.plover.com&#x2F;prog&#x2F;haskell&#x2F;probmonad-refs.html</a><p>[3]: <a href="http:&#x2F;&#x2F;journal.stuffwithstuff.com&#x2F;2015&#x2F;02&#x2F;01&#x2F;what-color-is-your-function&#x2F;" rel="nofollow">http:&#x2F;&#x2F;journal.stuffwithstuff.com&#x2F;2015&#x2F;02&#x2F;01&#x2F;what-color-is-y...</a>