Rust SDK

alien-sdk is the crate for Rust code that runs in a deployment: access to linked resources, plus commands, event handlers, and background tasks with the worker feature.

use alien_sdk::Bindings;

#[tokio::main(flavor = "current_thread")]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let bindings = Bindings::from_env()?;
    let cache = bindings.kv("cache").await?;
    cache.put("greeting", b"hello".to_vec(), None).await?;
    Ok(())
}

This page documents version 3.3.41. You still declare the stack in TypeScript (alien.ts); build the Rust binary with the rust toolchain ({ type: "rust", binaryName: "api" }).

InstallCopy Anchor Link

[dependencies]
alien-sdk = { version = "3.3.41", features = ["worker"] }
tokio = { version = "1", features = ["full"] }

BindingsCopy Anchor Link

Bindings::from_env() reads the bindings Alien injects for each linked resource. Each accessor is async and takes the resource ID from alien.ts:

The value and option types (KvEntry, PutOptions, QueueMessage, ScanResult, CreateSandboxRequest, RunCommandRequest) are in alien_sdk::traits. Errors are alien_sdk::error::Error, which carries a machine-readable code and a retryable flag.

Worker contextCopy Anchor Link

With the worker feature, AlienContext connects to the Worker runtime. Register handlers, register your HTTP server, then run the event loop:

use alien_sdk::worker::AlienContext;
use axum::{routing::get, Json, Router};
use serde_json::{json, Value};
use std::sync::Arc;

#[tokio::main]
async fn main() -> anyhow::Result<()> {
    let ctx = Arc::new(AlienContext::from_env().await?);

    ctx.on_command("echo", |params: Value| async move { Ok(params) });

    let app = Router::new().route("/health", get(|| async { Json(json!({ "status": "ok" })) }));
    let listener = tokio::net::TcpListener::bind("0.0.0.0:0").await?;
    ctx.register_http_server(listener.local_addr()?.port()).await?;

    let events = ctx.clone();
    tokio::spawn(async move { events.run().await });

    axum::serve(listener, app).await?;
    Ok(())
}

The server binds to port 0 and reports the chosen port to the runtime with register_http_server.

NextCopy Anchor Link

• Resources: options and limits for each resource
• Worker: triggers and the rust toolchain
• TypeScript SDK