You misunderstood me. I wasn&#x27;t saying that it eliminated side effects. I was saying that it brought no great advances with respect to side effects, and most people write code that <i>mostly</i> only does side effects. This is why OO had such a great impact on the business world and functional programming didn&#x27;t.<p>It&#x27;s actually pretty rare for businesses to write highly complex <i>mostly</i> functional code (a spam filter is one exception), and that is where Haskell really shines.<p>&gt;I would suggest you actually spend some time with the language in anger. It is not easy. But I&#x27;ve been writing &#x27;real world&#x27; software in Haskell for years, and it&#x27;s no more difficult or &#x27;magical&#x27; than any other part of being a software developer. It&#x27;s just more rewarding because my code works far more often. And working code seems to be something that&#x27;s rare in the software world these days<p>I&#x27;ve tried it and I&#x27;ve seen its advantages and I&#x27;m content to remain with python for the time being. Python&#x27;s type system isn&#x27;t as good and that does sometimes cause bugs I wouldn&#x27;t get in Haskell which I fully understand, but I&#x27;d consider the difference incremental. It&#x27;s not any kind of great leap forward and I think my code would only be slightly less buggy in equivalent Haskell.<p>On the other hand, Python has a wealth of packages and an ecosystem that Haskell simply doesn&#x27;t even come close to matching.<p>Stable, working code is rare, I&#x27;ll grant you that, and weaker type systems definitely make programming more of a balancing act, but there&#x27;s a trade off to be made between stronger type systems and not having to rewrite a ton of working code which already exists.