Async, Concurrency & Runtimes Packages
Async runtimes, concurrency primitives, and futures for writing non-blocking, parallel, and highly concurrent programs (Tokio, futures, asyncio helpers).
Packages in Async, Concurrency & Runtimes
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aiosqlite
Async/await-friendly wrapper around Python's built-in sqlite3 module for asyncio applications.
httpcore
A minimal, low-level HTTP client for Python with sync, async, and HTTP/2 support
num_cpus
A small Rust crate for counting the logical and physical CPU cores on the current machine.
sniffio
A tiny Python library that detects which async framework (trio, asyncio, or curio) your code is currently running under.
Comlink
A tiny RPC library that makes Web Workers enjoyable to use in JavaScript
APScheduler
Python task scheduler with cron, interval, and one-off triggers, backed by pluggable persistent datastores for distributed job scheduling.
bluebird
A drop-in Promises/A+ implementation engineered for raw execution speed, long stack traces, and a rich set of async collection utilities.
asgiref
Async/sync bridging utilities and the reference toolkit behind the ASGI spec, maintained by the Django project.
crossbeam
A collection of tools for lock-free and concurrent programming in Rust: channels, deques, epoch-based GC, and more
backoff
Python function decorators that retry calls on exceptions or bad return values, with exponential, fibonacci, or constant backoff and jitter.
p-retry
Retry a promise-returning or async function with exponential backoff and fine-grained retry control.
pin-project
Safe, ergonomic pin projection for Rust structs and enums
ArcSwap
Lock-free atomically swappable Arc for Rust read-mostly workloads
nest_asyncio
Patch asyncio to allow nested event loops in Jupyter, web servers, and GUIs
gevent
Coroutine-based concurrency for Python, built on greenlets and a fast libev/libuv event loop.
redsync
A Go implementation of the Redlock distributed locking algorithm for coordinating mutual exclusion across multiple Redis instances.
Moka
Fast, concurrent in-memory caching library for Rust, inspired by Java's Caffeine
async-timeout
An asyncio-compatible timeout context manager for Python, now superseded by stdlib asyncio.timeout
tokio-rustls
Asynchronous TLS/SSL streams for the Tokio runtime, built on Rustls
watchfiles
Simple, modern, and fast file watching and code-reload for Python, powered by a Rust core built on the `notify` crate
aiosignal
A lightweight async callback registry that turns a mutable list of coroutine receivers into a frozen, awaitable dispatch signal.
frozenlist
A list-like Python type that can be frozen at runtime to guard shared state from further mutation.
aiohappyeyeballs
Happy Eyeballs (RFC 8305) connection racing for asyncio when you already have resolved addresses
console-subscriber
tracing-subscriber Layer that powers tokio-console, a debugger for async Rust
