#[export]">

#[export]

The #[hyperactor::export] macro turns a regular Actor implementation into a remotely spawnable actor, registering its type information, spawn function, and supported message handlers for discovery and use across processes or runtimes.

What It Adds

When applied to an actor type like this:

#[hyperactor::export(
    spawn = true,
    handlers = [ShoppingList],
)]
struct ShoppingListActor(HashSet<String>);

The macro expands to include:

• A Named implementation for the actor

• A Binds<Self> implementation that registers supported message types

• Implementations of RemoteHandles<T> for each type in the handlers = [...] list

• A RemoteActor marker implementation

• If spawn = true, a RemotableActor implementation and an inventory registration of the spawn function.

This enables the actor to be:

• Spawned dynamically by name

• Routed to via typed messages

• Reflected on at runtime (for diagnostics, tools, and orchestration)

Generated Implementations (simplified)

impl RemoteActor for ShoppingListActor {}

impl RemoteHandles<ShoppingList> for ShoppingListActor {}
impl RemoteHandles<Signal> for ShoppingListActor {}

impl Binds<ShoppingListActor> for ShoppingListActor {
    fn bind(ports: &Ports<Self>) {
        ports.bind::<ShoppingList>();
    }
}

impl Named for ShoppingListActor {
    fn typename() -> &'static str {
        "my_crate::ShoppingListActor"
    }
}

If spawn = true, the macro also emits:

impl RemotableActor for ShoppingListActor {}

This enables remote spawning via the default gspawn provided by a blanket implementation.

It also registers the actor into inventory:

inventory::submit!(SpawnableActor {
    name: ...,
    gspawn: ...,
    get_type_id: ...,
});

This allows the actor to be discovered and spawned by name at runtime.

Summary

The #[export] macro makes an actor remotely visible, spawnable, and routable by declaring:

• What messages it handles

• What messages it handles

• How to bind those messages

• What its globally unique name is

• (Optionally) how to spawn it dynamically