caravan-rpc (Rust) — Pre-release placeholder

Runtime SDK for the Caravan application-definition compiler.

Status: 0.0.1 pre-release placeholder. This release reserves the crates.io name. The functional SDK lands at 0.1.0.

What is Caravan?

Caravan is an application-definition compiler. The same source code deploys across packaging (inproc / container / lambda) × placement (compose / Fargate / Lambda / Batch) × composition (oss-local / cloud-managed) axes by yaml-line changes alone — no source-code edits.

Read the thesis and the PoC RPC SDK spec.

When 0.1.0 ships

use caravan_rpc::{wagon, provide, client};

#[wagon]
#[async_trait::async_trait]
pub trait Embedder: Send + Sync {
    async fn embed(&self, text: String) -> Vec<f32>;
}

// provider side
struct FastEmbedImpl { /* ... */ }

#[async_trait::async_trait]
impl Embedder for FastEmbedImpl {
    async fn embed(&self, text: String) -> Vec<f32> { /* ... */ }
}

fn register() {
    provide::<dyn Embedder>(Arc::new(FastEmbedImpl::new()));
}

// caller side — dispatches inproc / http / lambda per CARAVAN_RPC_PEERS
async fn use_embedder() {
    let embedder = client::<dyn Embedder>();
    let v = embedder.embed("hello".into()).await;
}

The 0.0.1 placeholder exposes wagon / provide / client as no-op functions; client() panics.

Roadmap

• 0.0.1 (this release): reserve crates.io name, build-clean stubs.
• 0.1.0: functional runtime with #[wagon] proc-macro, axum HTTP server adapter, Lambda Function URL client adapter, CARAVAN_RPC_PEERS env-var dispatch. See development_plan.md milestone M2.

License

Apache-2.0. See LICENSE.