Technically, a Polylith interface is a collection of "pass-through" functions, each of which delegate their function call to an "implementation" function within

Technically, a Polylith interface is a collection of "pass-through" functions, each of which delegate their function call to an "implementation" function within the component. I agree with you that many languages have syntax to support building interfaces. However, I've yet to come across one that offers all the benefits of Polylith's approach with components.