# Closure Library [![Build Status](https://travis-ci.org/google/closure-library.svg?branch=master)](https://travis-ci.org/google/closure-library)
Closure Library is a powerful, low-level JavaScript library designed
for building complex and scalable web applications. It is used by many
Google web applications, such as Google Search, Gmail, Google Docs,
Google+, Google Maps, and others.
For more information, visit the
[Google Developers](https://developers.google.com/closure/library) or
[GitHub](https://github.com/google/closure-library) sites.
Download the latest stable version on our [releases page](https://github.com/google/closure-library/releases).
Developers, please see the
[Generated API Documentation](https://google.github.io/closure-library/api/).
See also the
[goog.ui Demos](https://google.github.io/closure-library/source/closure/goog/demos/)
## Using with Node.js
Install the [official package](https://www.npmjs.com/package/google-closure-library) from npm.
```bash
npm install google-closure-library
```
Require the package and use goog.require normally.
```js
require("google-closure-library");
goog.require("goog.crypt.Sha1");
var sha1 = new goog.crypt.Sha1();
sha1.update("foobar");
var hash = sha1.digest();
```
## Contributing
Please read the [CONTRIBUTING] for details on how to contribute to this project.
[CONTRIBUTING]: https://github.com/google/closure-library/blob/master/CONTRIBUTING