I would argue that it isn't quite the same, since with Haskell you can enforce it with the type system. While other frameworks are great pieces of engineering a

I would argue that it isn't quite the same, since with Haskell you can enforce it with the type system. While other frameworks are great pieces of engineering and usually well tested, Haskell is nothing without it's type system therefore tons of work is put towards ensuring that what the type system says is true, is true. The other thing is I believe frameworks like Yesod use property based testing which IME catches a lot more than unit tests by themselves. I feel like my point is unclear here, perhaps someone more experienced with Haskell and/or Yesod can articulate it better than I can.