Tokio is an asynchronous runtime for the Rust programming language. It provides the building blocks for reliable, scalable, performant network applications: a multi-threaded work-stealing scheduler, async-aware versions of TCP/UDP/files/timers, and channels.
Tokio powers production systems at AWS, Discord, Cloudflare, Microsoft, Mozilla, and Dropbox — handling millions of concurrent connections with predictable latency.
Asynchronous Rust runtime. Reliable, scalable, fast. Powers production network services worldwide.
✨ Features
Multi-threaded async executor that balances tasks across cores. Predictable tail latencies.
Drop-in async TcpStream, UdpSocket, File. Cancellation-safe with structured timeouts.
mpsc, oneshot, broadcast, watch. Async Mutex, RwLock, Semaphore — no executor blocking.
Hierarchical timer wheel. Millions of concurrent timeouts handled efficiently.
Debug live task state and stalls like top(1) for async tasks. tracing integration built in.
