Overview

Orchis is a Rust library for building typed pipelines over distributed task queues. You chain tasks together declaratively, and the compiler verifies that every step’s output type matches the next step’s input. At runtime, each step executes on a remote worker via Redis Streams, and a middleware layer automatically advances the pipeline between steps.

#![allow(unused)]
fn main() {
let handle = Pipeline::new(broker)
    .first::<FetchPages>()
    .fan_out()
    .then::<ExtractContent>()
    .collect()
    .then::<GenerateSummary>()
    .dispatch(())
    .await?;

let summary: Summary = handle.wait_result(Duration::from_secs(60)).await?;
}

The pipeline above fetches pages, extracts content from each one in parallel across workers, gathers the results, and generates a summary. If ExtractContent expects a Page but FetchPages returns a Vec<String>, the code won’t compile.

Crates

• orchis-core: Broker-agnostic traits, operation types, typestate pipeline builder, and middleware.
• orchis-redis: Redis backend implementing Broker and BarrierBackend via fred, plus a stream-based worker with bounded concurrency.
• orchis-macros: #[task("name")] attribute that derives a Task implementation from an async function signature.