Macro local_system 

macro_rules! local_system {
    (mailbox = $mailbox:expr, routes = $routes:expr $(,)?) => { ... };
}

Construct the existing local bombay::System with named semantic inputs while preserving the concrete router type.

This macro expands directly to bombay::System::new; it creates no alternate runtime, spawn path, task, registry, or policy object.

use bombay_framework::{local_system, prelude::*};

let _: System<AddressRouter<MailAddr, ()>> = local_system!(
    mailbox = MailboxConfig::bounded(8),
    routes = AddressRouter::default(),
);

Named inputs intentionally reject misspellings at the authoring boundary:

use bombay_framework::{local_system, prelude::*};

let _ = local_system!(
    capacity = MailboxConfig::bounded(8),
    routes = AddressRouter::<MailAddr, ()>::default(),
);