alt Hacker NewsThere's probably a case for both. Core logic might benefit from hard types deep in the bowels of unchanging engine.
The real world often changes though, and more often than not the code has to adapt, regardless of how elegant are systems are designed.
Coalton ( https://coalton-lang.github.io ) is the sort of thing I like: a Haskell-style language hosted inside a very dynamic one with good interop.