vault/nerv: A blazing fast React alternative

Nerv is a virtual-dom based JavaScript (TypeScript) library with identical React 16 API, which offers much higher performance, tinier package size and better browser compatibility.

中文

Features

⚛ Identical React API, no ‘nerv-compat’ is needed

️⚔ Battle tested, serve in JD.com home page and TOPLIFE.com

⚡️ High performance

🤣 IE8 compatibility

🎯 Tiny size, 9Kb gzipped

🌗 Isomorphic rendering on both client and server

💫 Support React 16 features, Error Boundaries, Portals, custom DOM attributes, etc.

Packages

This repository is a monorepo that we manage using Lerna. That means that we actually publish several packages to npm from the same codebase, including:

Package	Description
`nervjs`	The core of Nerv
`nerv-redux`	Nerv binding for Redux
`nerv-devtools`	Provides support for React’s Dev Tools for Nerv
`nerv-server`	Support for server side rendering
`nerv-test-utils`	Suite of utilities for testing Nerv applications
`nerv-utils`	Internal Helpers functions for Nerv
`nerv-shared`	Internal shared functions for Nerv
`nerv-create-class`	The legacy `createClass` API for Nerv

Getting Started

The easiest way to get started with Nerv is using CodeSandbox Playground, If you use React, you already know how to use Nerv.

Install

Of course we recommend that you use Nerv with Webpack and Babel.First you can install Nerv like this

With npm

$ npm install --save nervjs

With yarn

$ yarn add nervjs

Usage

Import what you need. Nerv provides both named and default exports, you can use Nerv as a namespace or simply import what you need as locals.

Default exports:

import Nerv from 'nervjs'
class HelloMessage extends Nerv.Component {
  render() {
    return <div>Hello {this.props.name}</div>
  }
}

Nerv.render(
  <HelloMessage name="Nerv" />,
  document.getElementById('app')
)

Named:

import { Component, render } from 'nervjs'
class HelloMessage extends Component {
  render() {
    return <div>Hello {this.props.name}</div>
  }
}

render(
  <HelloMessage name="Nerv" />,
  document.getElementById('app')
)

☝️ For more information please move to the official development document

Examples

TodoMVC, built with Nerv and Redux
Nerv’s landing page, built with Nerv and react-intl
JD.com
TOPLIFE.com

Switching to Nerv from React

Switching to Nerv from React is easy as adding alias nervjs for react and react-dom. No changes in code needed.

Usage with Webpack

Add an alias in your webpack.config.js:

{
  // ...
  resolve: {
    alias: {
      'react': 'nervjs',
      'react-dom': 'nervjs',
      // Not necessary unless you consume a module using `createClass`
      'create-react-class': "nerv-create-class"
    }
  }
  // ...
}

Usage with Babel

Install the babel plugin for aliasing

$ npm install --save-dev babel-plugin-module-resolver

In .babelrc:

{
  "plugins": [
    ["module-resolver", {
      "root": ["."],
      "alias": {
        "react": "nervjs",
        "react-dom": "nervjs",
        // Not necessary unless you consume a module using `createClass`
        "create-react-class": "nerv-create-class"
      }
    }]
  ]
}

Usage with Browserify

Install the aliasify transform:

$ npm i --save-dev aliasify

Then in your package.json:

{
  "aliasify": {
    "aliases": {
      "react": "nervjs",
      "react-dom": "nervjs"
    }
  }
}

Compatible with React

Nerv currently support React API and features:

`react`

React.createClass (legacy)
React.createElement
React.cloneElement
React.Component
React.PureComponent
React.PropTypes
React.Children
React.isValidElement
React.createFactory
Error Boundaries (React 16)

`react-dom`

React.unstable_renderSubtreeIntoContainer (legacy)
ReactDOM.render
ReactDOM.unmountComponentAtNode
ReactDOM.findDOMNode
ReactDOM.hydrate (React 16)
ReactDOM.createPortal (React 16)

Internet Explorer 8 (or below) compatibility

First, install es5-polyfill:

npm install --save es5-polyfill

Then insert the code into the beginning of your entry file:

require('es5-polyfill');

At last, setting .babelrc if you are using babel:

{
  "presets": [
    ["env", {
      "spec": true,
      "useBuiltIns": false
    }],
    ["es3"]
  ],
  ...
}

Developer Tools

Nerv has a development tools module which allows you to inspect the component hierarchies via the React Chrome Developer Tools plugin.

To enable the Nerv development tools you must install the nerv-devtools module and then require('nerv-devtools') before the initial Nerv.render().

if (process.env.NODE_ENV !== 'production')  {
  require('nerv-devtools')
}
// before Nerv.render()
Nerv.render(<App />, document.getElementById('#root'))