Tokio
A runtime for writing reliable, asynchronous, and slim applications with the Rust programming language. It is:
-
Fast: Tokio's zero-cost abstractions give you bare-metal performance.
-
Reliable: Tokio leverages Rust's ownership, type system, and concurrency model to reduce bugs and ensure thread safety.
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Scalable: Tokio has a minimal footprint, and handles backpressure and cancellation naturally.
Website | Guides | API Docs | Chat
Overview
Tokio is an event-driven, non-blocking I/O platform for writing asynchronous applications with the Rust programming language. At a high level, it provides a few major components:
- A multithreaded, work-stealing based task scheduler.
- A reactor backed by the operating system's event queue (epoll, kqueue, IOCP, etc...).
- Asynchronous TCP and UDP sockets.
These components provide the runtime components necessary for building an asynchronous application.
Example
To get started, add the following to Cargo.toml
.
= { = "0.2", = ["full"] }
Tokio requires components to be explicitly enabled using feature flags. As a
shorthand, the full
feature enables all components.
A basic TCP echo server with Tokio:
use TcpListener;
use *;
async
More examples can be found here.
Getting Help
First, see if the answer to your question can be found in the Guides or the API documentation. If the answer is not there, there is an active community in the Tokio Discord server. We would be happy to try to answer your question. Last, if that doesn't work, try opening an issue with the question.
Contributing
:balloon: Thanks for your help improving the project! We are so happy to have you! We have a contributing guide to help you get involved in the Tokio project.
Related Projects
In addition to the crates in this repository, the Tokio project also maintains several other libraries, including:
-
tracing
(formerlytokio-trace
): A framework for application-level tracing and async-aware diagnostics. -
mio
: A low-level, cross-platform abstraction over OS I/O APIs that powerstokio
. -
bytes
: Utilities for working with bytes, including efficient byte buffers.
Supported Rust Versions
Tokio is built against the latest stable, nightly, and beta Rust releases. The minimum version supported is the stable release from three months before the current stable release version. For example, if the latest stable Rust is 1.29, the minimum version supported is 1.26. The current Tokio version is not guaranteed to build on Rust versions earlier than the minimum supported version.
License
This project is licensed under the MIT license.
Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in Tokio by you, shall be licensed as MIT, without any additional terms or conditions.