Qubit Execution Services

Aggregate execution-service facade for Rust applications.

Overview

Qubit Execution Services wires together the Qubit executor implementations that an application commonly needs: blocking OS-thread work, CPU-bound Rayon work, Tokio blocking work, and async IO futures.

This crate is an application-level convenience facade. It is not the foundational abstraction layer. Libraries should usually depend on smaller crates such as qubit-executor, qubit-thread-pool, qubit-rayon-executor, or qubit-tokio-executor directly.

Features

• ExecutionServices facade with separate blocking, CPU, Tokio blocking, and async IO domains.
• ExecutionServicesBuilder for configuring the blocking thread-pool domain and CPU Rayon domain.
• submit_blocking and submit_blocking_callable for general synchronous blocking work.
• submit_cpu and submit_cpu_callable for CPU-bound work routed to Rayon.
• submit_tokio_blocking and submit_tokio_blocking_callable for blocking functions routed through Tokio.
• spawn_io for async futures routed through Tokio's async scheduler.
• ExecutionServicesShutdownReport for aggregating queued, running, and cancelled counts across all domains.
• Type aliases and re-exports for the underlying executor services and task handles.

Execution Domains

The blocking domain uses ThreadPool from qubit-thread-pool. It is intended for synchronous work that may block OS threads, such as filesystem operations or legacy blocking APIs.

The CPU domain uses RayonExecutorService from qubit-rayon-executor. It is intended for CPU-heavy work where Rayon scheduling is the right execution model.

The Tokio blocking domain uses TokioExecutorService from qubit-tokio-executor. It is intended for blocking functions submitted from a Tokio application and executed through spawn_blocking.

The IO domain uses TokioIoExecutorService from qubit-tokio-executor. It is intended for async futures and non-blocking IO work executed through tokio::spawn.

Builder Configuration

ExecutionServicesBuilder delegates blocking-domain settings to ThreadPoolBuilder and CPU-domain settings to RayonExecutorServiceBuilder. Tokio-backed domains currently use their default constructors because Tokio owns the runtime and scheduler configuration.

The builder exposes common blocking-pool controls such as pool size, core size, maximum size, queue capacity, thread-name prefix, stack size, keep-alive, core-thread timeout, and prestart behavior. It also exposes CPU-domain controls for Rayon worker count, thread-name prefix, and stack size.

Shutdown Behavior

shutdown requests orderly shutdown for every domain. New tasks are rejected, and accepted work is allowed to complete according to each underlying service.

shutdown_now requests immediate shutdown for every domain and returns an ExecutionServicesShutdownReport containing one ShutdownReport per domain. The report also provides total_queued, total_running, and total_cancelled helpers for aggregate accounting.

await_termination resolves after every underlying service has terminated.

Quick Start

use std::io;

use qubit_execution_services::ExecutionServices;

# async fn run() -> Result<(), Box<dyn std::error::Error>> {
let services = ExecutionServices::builder()
    .blocking_pool_size(4)
    .blocking_queue_capacity(1024)
    .cpu_threads(4)
    .build()?;

let blocking = services.submit_blocking_callable(|| Ok::<usize, io::Error>(40 + 2))?;
let cpu = services.submit_cpu_callable(|| Ok::<usize, io::Error>((1..=10).sum()))?;
let io = services.spawn_io(async { Ok::<usize, io::Error>(6 * 7) })?;

assert_eq!(blocking.get()?, 42);
assert_eq!(cpu.get()?, 55);
assert_eq!(io.await?, 42);

services.shutdown();
services.await_termination().await;
# Ok(())
# }

Choosing a Dependency

Use qubit-execution-services at application boundaries when one owned facade should route different task types to different execution domains.

Use a smaller crate directly when you only need one layer or one runtime:

• qubit-executor for traits, task handles, and shared lifecycle types.
• qubit-thread-pool for runtime-independent OS-thread pools.
• qubit-rayon-executor for CPU-bound Rayon execution.
• qubit-tokio-executor for Tokio blocking and async IO execution.

Testing

A minimal local run:

cargo test
cargo clippy --all-targets --all-features -- -D warnings

To mirror what continuous integration enforces, run the repository scripts from the project root: ./align-ci.sh brings local tooling and configuration in line with CI, then ./ci-check.sh runs the same checks the pipeline uses. For test coverage, use ./coverage.sh to generate or open reports.

Contributing

Issues and pull requests are welcome.

• Open an issue for bug reports, design questions, or larger feature proposals when it helps align on direction.
• Keep pull requests scoped to one behavior change, fix, or documentation update when practical.
• Before submitting, run ./align-ci.sh and then ./ci-check.sh so your branch matches CI rules and passes the same checks as the pipeline.
• Add or update tests when you change runtime behavior, and update this README or public rustdoc when user-visible API behavior changes.
• If you change routing or shutdown behavior, include tests that verify every affected execution domain.

By contributing, you agree to license your contributions under the Apache License, Version 2.0, the same license as this project.

License

Copyright © 2026 Haixing Hu, Qubit Co. Ltd.

This project is licensed under the Apache License, Version 2.0. See the LICENSE file in the repository for the full text.

Author

Haixing Hu — Qubit Co. Ltd.