Haskell certainly is not the pinnacle in language design. IMHO it is the first successfully implemented research language, though. I think that Haskell is the

Haskell certainly is not the pinnacle in language design. IMHO it is the first successfully implemented research language, though. I think that Haskell is the first language that, at the same time, had substantial commercial and research applications[1]. As such, it showed that the CS of PL is indeed of practical relevance. Rust on the other hand, mostly applies this scientific research. And successfully so. Hence I call it the "engineering" part. [1] To a certain degree this is also true for Lisp and SML, of course. But I think SML fell out of fashion quite quickly both in academia and industry. Lisp is, well, lisp. People that start using it seldom search for another language afterwards.