unenv

unenv is a framework agnostic system that allows converting JavaScript code to be platform agnostic and working in any environment including Browsers, Workers, Node.js or pure JavaScript runtime.

Install

# Using npm
npm i -D unenv

# Using yarn
yarn add --dev unenv

# Using pnpm
pnpm add -D unenv

Usage

Using env utility and built-in presets (and nodeless), unenv will provide an abstract configuration that can be used in building pipelines (rollup.js, webpack, etc.).

import { env, node, nodeless } from "unenv";

const { alias, inject, polyfill, external } = env(...presets);

Presets

node

Suitable to convert universal libraries working in Node.js. (preset)

• Add supports for global fetch API
• Set Node.js built-ins as externals

nodeless

Using this preset, we can convert a code that is depending on Node.js to work anywhere else.

Built-in Node.js modules

unenv provides a replacement for all Node.js built-ins for cross-platform compatiblity.

npm packages

unenv provides a replacement for common npm packages for cross platform compatibility.

Auto-mocking proxy

import MockProxy from "unenv/runtime/mock/proxy";

console.log(MockProxy().foo.bar()[0]);

Above package doesn't work outside of Node.js and neither we need any platform specific logic! When aliasing os to mock/proxy-cjs, it will be auto mocked using a Proxy Object which can be recursively traversed like an Object, called like a Function, Iterated like an Array, or instantiated like a Class.

We use this proxy for auto mocking unimplemented internals. Imagine a package does this:

const os = require("os");
if (os.platform() === "windows") {
  /* do some fix */
}
module.exports = () => "Hello world";

By aliasing os to unenv/runtime/mock/proxy-cjs, code will be compatible with other platforms.

Other polyfills

Please check ./src/runtime to discover other polyfills.

License

MIT