"Zephir extensions can even override core functions, with better-performing versions." Where to start?

Hey,

I have a use-case that zephir might be able to help with but I don't know where to start. I'd like to override the core mail() function and add a default header. Is this possible? The quote in the title was ripped from Typed PHP: Stronger Types for cleaner code.

To override a core function you have to create a custom optimizer. Please refer to https://docs.zephir-lang.com/en/latest/optimizers.html