---
title: Introduction
package: Dev
order_number: 1
---
The _Dev_ package provides core functionality for local development: installing dependencies, building your site, and triggering rebuilds live as you edit.

![](/images/gulp-dev-aviator.gif){: .demonstration}

### Features

* _Browsersync_ automatically refreshes your browser as you make edits, so you can see your changes and iterate quickly.
* Dev watches your `_config.yml` for changes, so you don't have to manually restart every time your configuration changes.
* Dev automatically detects the directory of your Jekyll theme, and watches it for changes