Polymer Logo Home Guides Feature overview Try Polymer Install Polymer 3.x Tutorial: Build an element 1. Get set up 2. Add shadow DOM 3. Data binding & properties 4. React to input 5. Theming with custom properties About this release What's new in 3.0 Upgrade guide Release notes Custom elements Custom element concepts Define an element Declare properties Working with legacy elements Shadow DOM & styling Shadow DOM concepts DOM templating Style shadow DOM Custom CSS properties Events Handle and fire events Gesture events Data system Data system concepts Work with object and array data Observers and computed properties Data binding Helper elements Browser support Overview Polyfills ES6 and modules Tools Tools overview Polymer CLI CLI commands Create an element project Create an application project Document your elements Test your elements polymer.json specification Node support Build apps Overview App templates Build for production Serve your app The PRPL pattern Service worker Reference Glossary Global settings API Reference index polymer-element.js Elements array-selector.js custom-style.js dom-bind.js dom-if.js dom-module.js dom-repeat.js Mixins dir-mixin.js disable-upgrade-mixin.js element-mixin.js gesture-event-listeners.js mutable-data.js properties-changed.js properties-mixin.js property-accessors.js property-effects.js strict-binding-parser.js template-stamp.js Utils array-splice.js async.js case-map.js debounce.js flattened-nodes-observer.js flush.js gestures.js html-tag.js mixin.js path.js render-status.js resolve-url.js settings.js style-gather.js telemetry.js templatize.js Legacy class.js legacy-data-mixin.js legacy-element-mixin.js mutable-data-behavior.js polymer-fn.js polymer.dom.js templatizer-behavior.js

The Polymer library is in maintenance mode. For new development, we recommend Lit.

Contents

This chapter describes how to install the Polymer 3.0 tools and get started with a template Polymer 3.0 project.

To set up a development environment for Polymer 3.0:

Download and run a Git installer for your operating system.

See the Git documentation for detailed instructions on installing Git.

To confirm that Git is correctly installed:

git --version

Download and run a Node.js installer for your operating system. This will install npm as well.

For more detailed instructions on installing npm and Node.js, see the npm and Node.js install documentation.

Install a current or active LTS version of Node.js. Polymer requires a current or active LTS version of Node.js. See our Node.js support page for more information.

To confirm that npm is correctly installed:

npm --version

To confirm that Node.js is correctly installed:

node --version

To install Polymer CLI, run the following command:

npm install -g polymer-cli

To confirm that the Polymer CLI has been correctly installed:

polymer --version

To test your Polymer development environment, you can try out a sample Polymer app we prepared earlier:

git clone https://github.com/PolymerLabs/start-polymer3.git
cd start-polymer3
npm install
polymer serve

For more information on the tools and options in the Polymer CLI, see the documentation on Polymer CLI commands.