I suspect that this is an area where Rust shines in a way I haven&#x27;t seen described for other functional languages, so I don&#x27;t know if it&#x27;s as relevant to people working in those other languages, but I haven&#x27;t really written anything performance sensitive <i>and</i> functionally-styled except in Rust.<p>Anecdotally, I have found a couple of times that I needed to manually implement a beautifully simple map&#x2F;filter&#x2F;fold call sequence in Rust because it was in a hot loop and just wasn&#x27;t performing as well as a dynamic programming version that I wrote in the course of benchmarking. I&#x27;ve also found that plenty of times the functional style beat my hand-rolled code, which is an absolutely fantastic result, but I don&#x27;t think that the compiler is yet sufficiently intelligent to replace <i>all</i> of my hand-rolled loops :).