The other half is the magic that worries me ;) And I'm not picking on Haskell here, I've lost countless hours to weird Spring failures when multiple annotation

The other half is the magic that worries me ;) And I'm not picking on Haskell here, I've lost countless hours to weird Spring failures when multiple annotations on one class or method interact poorly and produce a stack-trace deep in the bowels of Spring's annotation processors. Or, well, gestures at Hibernate in general Likewise, Django classes that defy type annotations because they override __new__ and inject nested classes into types, or queries over joins where the join logic between attribute A and type B is magically parsed from an undeclared keyword argument like "A__B__filter" that includes attributes, types and actions in one convenient keyword that no IDE can predict. Like your unevaluated thunks, trying to figure out why "Foo__Bar__bomb_baghdad" didn't actually bomb Baghdad takes a large amount of time. The magic is convenient until it breaks :)