lit-cli

Lit

Lit Apps with no build configuration.

• Getting Started – How to create a new app.
• User Guide – How to develop apps bootstrapped with Lit.

Lit works on macOS, Windows, and Linux.
If something doesn’t work, please file an issue.

Quick Overview

npm install -g lit

lit my-app
cd my-app/
npm start

Then open http://localhost:3000/ to see your app.
When you’re ready to deploy to production, create a minified bundle with npm run build.

Get Started Immediately

You don’t need to install or configure tools like Webpack or Babel.
They are preconfigured and hidden so that you can focus on the code.

Just create a project, and you’re good to go.

Getting Started

Installation

Install it once globally:

npm install -g lit

You’ll need to have Node >= 6 on your machine. You can use nvm to easily switch Node versions between different projects.

This tool doesn’t assume a Node backend. The Node installation is only required for Lit itself.

Creating an App

To create a new app, run:

lit my-app
cd my-app

It will create a directory called my-app inside the current folder.
Inside that directory, it will generate the initial project structure and install the transitive dependencies:

my-app
├── README.md
├── node_modules
├── package.json
├── .gitignore
├── public
│   └── favicon.ico
│   └── index.html
│   └── manifest.json
└── src
    └── App.css
    └── App.js
    └── App.test.js
    └── index.css
    └── index.js
    └── logo.svg
    └── registerServiceWorker.js

No configuration or complicated folder structures, just the files you need to build your app.
Once the installation is done, you can run some commands inside the project folder:

npm start or yarn start

Runs the app in development mode.
Open http://localhost:3000 to view it in the browser.

The page will automatically reload if you make changes to the code.
You will see the build errors and lint warnings in the console.

npm test or yarn test

Runs the test watcher in an interactive mode.
By default, runs tests related to files changed since the last commit.

Read more about testing.

npm run build or yarn build

Builds the app for production to the build folder.
It correctly bundles React in production mode and optimizes the build for the best performance.

The build is minified and the filenames include the hashes.
By default, it also includes a service worker so that your app loads from local cache on future visits.

Your app is ready to be deployed.

User Guide

The User Guide includes information on different topics, such as:

• Updating to New Releases
• Folder Structure
• Available Scripts
• Supported Language Features and Polyfills
• Syntax Highlighting in the Editor
• Displaying Lint Output in the Editor
• Formatting Code Automatically
• Debugging in the Editor
• Changing the Page <title>
• Installing a Dependency
• Importing a Component
• Code Splitting
• Adding a Stylesheet
• Post-Processing CSS
• Adding a CSS Preprocessor (Sass, Less etc.)
• Adding Images, Fonts, and Files
• Using the public Folder
• Using Global Variables
• Adding Bootstrap
• Adding Flow
• Adding Custom Environment Variables
• Can I Use Decorators?
• Integrating with an API Backend
• Proxying API Requests in Development
• Using HTTPS in Development
• Generating Dynamic <meta> Tags on the Server
• Pre-Rendering into Static HTML Files
• Running Tests
• Developing Components in Isolation
• Making a Progressive Web App
• Analyzing the Bundle Size
• Deployment
• Advanced Configuration
• Troubleshooting

A copy of the user guide will be created as README.md in your project folder.

How to Update to New Versions?

Please refer to the User Guide for this and other information.

Philosophy

• One Dependency: There is just one build dependency. It uses Webpack, Babel, ESLint, and other amazing projects, but provides a cohesive curated experience on top of them.

• No Configuration Required: You don't need to configure anything. Reasonably good configuration of both development and production builds is handled for you so you can focus on writing code.

• No Lock-In: You can “eject” to a custom setup at any time. Run a single command, and all the configuration and build dependencies will be moved directly into your project, so you can pick up right where you left off.

Why Use This?

If you’re getting started with React, use lit to automate the build of your app. There is no configuration file, and react-scripts is the only extra build dependency in your package.json. Your environment will have everything you need to build a modern React app:

• React, JSX, ES6, and Flow syntax support.
• Language extras beyond ES6 like the object spread operator.
• A dev server that lints for common errors.
• Import CSS and image files directly from JavaScript.
• Autoprefixed CSS, so you don’t need -webkit or other prefixes.
• A build script to bundle JS, CSS, and images for production, with sourcemaps.
• An offline-first service worker and a web app manifest, meeting all the Progressive Web App criteria.

The feature set is intentionally limited. It doesn’t support advanced features such as server rendering or CSS modules. The tool is also non-configurable because it is hard to provide a cohesive experience and easy updates across a set of tools when the user can tweak anything.

You don’t have to use this. Historically it has been easy to gradually adopt React. However many people create new single-page React apps from scratch every day. We’ve heard loud and clear that this process can be error-prone and tedious, especially if this is your first JavaScript build stack. This project is an attempt to figure out a good way to start developing React apps.

Converting to a Custom Setup

If you’re a power user and you aren’t happy with the default configuration, you can “eject” from the tool and use it as a boilerplate generator.

Running npm run eject copies all the configuration files and the transitive dependencies (Webpack, Babel, ESLint, etc) right into your project so you have full control over them. Commands like npm start and npm run build will still work, but they will point to the copied scripts so you can tweak them. At this point, you’re on your own.

Note: this is a one-way operation. Once you eject, you can’t go back!

You don’t have to ever use eject. The curated feature set is suitable for small and middle deployments, and you shouldn’t feel obligated to use this feature. However we understand that this tool wouldn’t be useful if you couldn’t customize it when you are ready for it.

Limitations

Some features are currently not supported:

• Server rendering.
• Some experimental syntax extensions (e.g. decorators).
• CSS Modules (see #2285).
• Importing LESS or Sass directly (but you still can use them).
• Hot reloading of components.

Some of them might get added in the future if they are stable, are useful to majority of React apps, don’t conflict with existing tools, and don’t introduce additional configuration.

What’s Inside?

The tools used by Lit are subject to change. Currently it is a thin layer on top of many amazing community projects, such as:

• webpack with webpack-dev-server, html-webpack-plugin and style-loader
• Babel with ES6 and extensions used by Facebook (JSX, object spread, class properties)
• Autoprefixer
• ESLint
• Jest
• and others.

All of them are transitive dependencies of the provided npm package.

Contributing

We'd love to have your helping hand on lit! See CONTRIBUTING.md for more information on what we're looking for and how to get started.

React Native

Looking for something similar, but for React Native?
Check out Create React Native App.

Acknowledgements

We are grateful to the authors of existing related projects for their ideas and collaboration:

• @eanplatter
• @insin
• @mxstbr

Alternatives

If you don’t agree with the choices made in this project, you might want to explore alternatives with different tradeoffs.
Some of the more popular and actively maintained ones are:

• insin/nwb
• mozilla-neutrino/neutrino-dev
• jaredpalmer/razzle
• NYTimes/kyt
• zeit/next.js
• gatsbyjs/gatsby
• electrode-io/electrode

Notable alternatives also include:

• enclave
• motion
• quik
• sagui
• roc
• aik
• react-app
• dev-toolkit
• sku
• gluestick

You can also use module bundlers like webpack and Browserify directly.
React documentation includes a walkthrough on this topic.