# Usage After creating a Firebase project and installing the library, we can use it in our project by importing the library in our JavaScript: ```javascript import RNFirebase from 'react-native-firebase' ``` We need to tell the Firebase library we want to _configure_ the project. RNFirebase provides a way to configure both the native and the JavaScript side of the project at the same time with a single command: ```javascript const firebase = RNFirebase.initializeApp({ // config options }); ``` ## Configuration Options | option | type | Default Value | Description | |----------------|----------|-------------------------|----------------------------------------| | debug | bool | false | When set to true, RNFirebase will log messages to the console and fire `debug` events we can listen to in `js` | | persistence | bool | false | When set to true, database persistence will be enabled. | | errorOnMissingPlayServices | bool | true | (Android only) When set to true, will throw an error if Google Play Services isn't installed. | | promptOnMissingPlayServices | bool | true | (Android only) When set to true, will prompt the user to install Google Play Services if it isn't installed. This takes precedence over `errorOnMissingPlayServices`.| For instance: ```javascript import RNFirebase from 'react-native-firebase'; const configurationOptions = { debug: true }; const firebase = RNFirebase.initializeApp(configurationOptions); export default firebase; ```