"Wrappers like Error considered harmful"

That is, people will go around and say "exceptions suck, lets use some object like Error so we can tangle up our happy paths and unhappy paths." Most of the time you find that error handling is absent or seriously deficient when people use Error(s) and similar things. This blog post finds the usual scenario: one web framework is almost right, the others aren't even in wrong.

Now Rust does have particular reasons why the happy and unhappy paths shouldn't diverge too much because otherwise the memory management problem gets harder.