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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backon
Retry any Rust function, sync or async, with exponential, fibonacci, or constant backoff strategies chained directly onto the call.
leaktest
A small Go package that detects leaked goroutines in tests by diffing stack snapshots taken before and after each test runs.
grpclib
A pure-Python gRPC implementation for asyncio built on top of the hyper-h2 HTTP/2 stack.
async-lru
Async LRU cache decorator for asyncio, ported from functools.lru_cache with TTL, jitter, and call de-duplication.
throng
A dead-simple one-liner for clustering Node.js apps across every CPU core.
cls-hooked
Continuation-local storage for Node.js, built on async_hooks instead of the deprecated async-listener.
ember-concurrency
Cancelable, restartable async task primitives for Ember.js that replace manual promise and flag juggling with declarative concurrency control.
async-compression
Async adaptors between Rust's compression crates and Tokio/futures IO traits
futures-concurrency
Performant, portable, structured concurrency operations for async Rust that work with any runtime.
async-recursion
A Rust procedural macro that makes recursive async functions compile by boxing their returned Future.
debounce-promise
Wrap any promise-returning function so rapid-fire calls collapse into one execution
p-debounce
Debounce promise-returning and async functions, sharing one resolved value across rapid calls.
@fastify/request-context
Request-scoped storage for Fastify apps, built on Node's AsyncLocalStorage, so any hook or handler can read and write per-request state without threading it through function arguments.
queue
Tiny, dependency-free async queue with concurrency control — faster and smaller than p-limit or fastq, with optional rate limiting.
ArcStr
A better reference-counted string type for Rust with zero-cost string literal support
leaky-bucket
An async Rust token-based rate limiter using the leaky bucket algorithm, with no dedicated background task required.
psycogreen
Wait-callback adapters that let psycopg2 run asynchronously under gevent or eventlet coroutine event loops.
aiocsv
Asynchronous CSV reading and writing for Python's asyncio, with a drop-in-compatible API and an optional C-accelerated parser.
fslock
Cross-platform file locking for Rust with blocking, non-blocking, and no_std support.
command-group
Rust extension trait that spawns child processes in a process group or Windows job object so you can control them as a unit.
actix
A Rust actor framework for building concurrent, message-driven systems on top of Tokio.
mio
A fast, low-level, non-blocking I/O library for Rust that wraps epoll, kqueue, and IOCP behind one cross-platform event-polling API.
oneTBB
Intel's oneAPI Threading Building Blocks — a task-based C++ parallelism library, with prebuilt binaries on PyPI.
Ratchet
Build realtime, bi-directional WebSocket applications between clients and servers in PHP.
