@mattly @snarfmason As someone who for years was totally in on dynamic typing (I was on the Smalltalk team at Apple, after all!) - I now see deep value in type systems for practical engineering projects.
BUT - they have to be real, strong type systems. Not "gradual" types, nor bolted on to dynamic languages.
With a strong type system (like Haskell's) - I've found real engineering projects benefit greatly from initial deployment, to staying bug free over their lifetime of enhancement.