TL;DR: The blogger took 4 Python projects, rewrote them in Haskell, and 3 of them had type errors. Therefore unit tests are not replacements for static typing.

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I don't get how this post says anything about unit testing or static typing at all. Doesn't it just imply that bugs are easier to detect with one method than another method? Most statically typed languages out there have a type system too weak to make the expression 1/0 a compile-time error. But you work around this with linting, unit tests, using a language with a stronger type system, etc.