"where I turn" This wording really hilights something that I think a lot of dynamic typing proponents don't fully appreciate. Using a type system is a learned skill, not something you magically get for free. You need both a good type system and the experience/education to use it to its fullest. Encoding threading rules in the type system isn't something C ships with out of the box, and it's not something a lot of people would think of, but moving that into the type system rather than relying on unit/manual test is a huge win.