pub trait Middleware<T>: Send + Sync {
// Provided methods
fn before<'a>(
&'a self,
ctx: &'a T,
) -> Pin<Box<dyn Future<Output = ()> + Send + 'a>> { ... }
fn after<'a>(
&'a self,
ctx: &'a T,
) -> Pin<Box<dyn Future<Output = ()> + Send + 'a>> { ... }
}