object-is

node's assert.deepEqual algorithm

ES6 spec-compliant RegExp.prototype.flags shim.

Get the byte length of an ArrayBuffer, even in engines without a `.byteLength` method.

Node.js path.parse() ponyfill

Reactive Extensions for modern JavaScript

A small polyfill for Object.setprototypeof

Is this value a JS regex? Works cross-realm/iframe, and despite ES6 @@toStringTag

An implementation of WHATWG AbortController interface.

Polyfills for React Native.

Check if the process is running inside Windows Subsystem for Linux (Bash on Windows)

Returns true if a string has an extglob.

Implementation of Function.prototype.bind

node's assert.deepEqual algorithm except for NaN being equal to NaN

The semantic version parser used by npm.

Store information about any JS value in a side channel. Uses WeakMap if available.

Is this value a JS regex? Works cross-realm/iframe, and despite ES6 @@toStringTag

Get an iterator for any JS language value. Works robustly across all environments, all versions.

Which kind of boxed JS primitive is this?

Get the byte length of an ArrayBuffer, even in engines without a `.byteLength` method.

Robustly `.call.bind()` a function

Array#isArray for older browsers

Is this an arguments object? It's a harder question than you think.

Is this value a JS SharedArrayBuffer?

An AST-based pattern checker for JavaScript.

Get and robustly cache all JS language-level intrinsics at first require time