Devs that have worked on large rust applications, how do you avoid needing circular references?

I'm interested specifically in server apps. When there's one source of input and one output, I find the borrow checker normally doesn't get in the way. But when dealing continuously with multiple sources of input, all of the designs I've worked with in other languages, have a lot of callbacks and circular references. I can't see an easy way of writing the same design in rust, without using a lot of Rc<RefCell<T>>.

How is this solved in practice? What solutions are used to avoid needing the dreaded circular reference?