In my experience, annotation processors are definitely way harder to reason about than def macros in Scala (especially blackbox ones). I find them to be about a

In my experience, annotation processors are definitely way harder to reason about than def macros in Scala (especially blackbox ones). I find them to be about as hard to reason about as macro annotations despite being less powerful. They are also way harder to write and distribute and not at all an analogue to typeclasses.