Open-source alternatives to Step

Bluebird is a JavaScript promise library designed for managing asynchronous operations with a custom promise implementation. It provides a framework for controlling promise lifecycles and orchestrating non-blocking programming patterns. The library distinguishes itself with an asynchronous debugging toolkit that captures long stack traces across asynchronous boundaries and a global handler for unhandled promise rejections. It includes a predicate-based error filtering system to target specific exception types and a mechanism for the deterministic cleanup of system resources. It covers a broa

:surfer: Asynchronous flow control with a functional taste to it

A solid, fast Promises/A+ and when() implementation, plus other async goodies.

Transform stream that lets you peek the first line before deciding how to parse it

Combine an array of streams into a single duplex stream using pump and duplexify

a fast newline (or any delimiter) splitter stream - like require('split') but specific for binary data

Memoize promise-returning functions. Includes cache expire and prefetch.

Node-core streams for userland

RxJS is a library for reactive programming that provides a framework for composing asynchronous and event-based programs. It utilizes observable sequences to model data flows, allowing developers to manage complex sequences of events through a declarative programming interface. The library implements the observer pattern to facilitate decoupled communication between data producers and subscribers. By employing a lazy execution model, streams remain dormant until a consumer explicitly subscribes, at which point data production is triggered. This approach enables the construction of predictable

Delay a promise a specified amount of time

Transform the first chunk in a stream

Get a stream as a string, Buffer, ArrayBuffer or array

Convert a string/promise/array/iterable/asynciterable/buffer/typedarray/arraybuffer/object into a stream

Convert an Observable to a Promise

Map over promises concurrently

Pad each line in a stream

Simple Node.JS stream (streams2) Transform that runs the transform functions concurrently (with a set max concurrency)

Promisify a callback-style function

High-level streams library for Node.js and the browser

A stream that emits multiple other streams one after another (streams3)

Convenience wrapper for ReadableStream, with an API lifted from "from" and "through2"

Line-by-line Stream reader for node.js

Limit the execution rate of a function

Turn a writable and readable stream into a streams2 duplex stream with support for async initialization and streams1/streams2 input