# start ## Description * Create a composite bundle out of multiple MiniApps and start the react-native local packager to serve this bundle so that it can be loaded within the native host application ## Syntax `ern start` **Note** If you do not pass an argument to this command, you are prompted to select a native application version from the Cauldron. The command uses whatever MiniApp versions are currently declared in this native application version container to launch the command. **Options** `--baseComposite ` * Git or File System path, to the custom Composite repository (refer to the [custom Composite](https://github.com/electrode-io/electrode-native/tree/ca91ff94ebe1206ee7deb9061a19a85f174ef43b/docs/cli/platform-parts/composite/index.md) documentation for more information). `--compositeDir ` * Directory in which to generate the composite * The directory should either not exist (will be created) or be empty * By default the composite will be generated in a temporary directory `--descriptor/-d ` * Target a specific native application version, associated to the provided *complete native application descriptor*. * This option uses whatever MiniApp versions are currently declared in this native application version container to launch the command. `--miniapps/-m ` * Specify one or more MiniApps to launch this command * The command packages all the provided MiniApps in a composite bundle and starts the react-native packager. * You can use any valid Yarn package descriptor for the MiniApps provided to this command, including Git and other file system path schemes. `--jsApiImpls` * Specify one or more JS API Implementations to include `--watchNodeModules/-w ` * A list of one or more directory name(s) from node\_modules that should be watched for changes. `--extraJsDependencies/-e ` * Additional JavaScript dependencies to add to the composite JavaScript bundle. `--host` * Host or ip to launch the local packager on *(default: localhost)* `--port` * Port on which the local packager should listen on *(default: 8081)* `--resetCache`\\ * Indicates whether to reset the React Native cache prior to bundling **Platform Specific Options** `Android` `--activityName/-a ` * Specify Android Activity to launch. `--launchFlags ` * Extra options passed to `am start` command when launching the application (correspond to the `Launch Flags` in Run/Debug Configurations of application in Android Studio, as can be seen on screenshot below) * Make sure to use `=` on the command line to provide this option, and keep the string in quotes. For example `--launchFlags="--es aKey aStringValue --ei anotherKey 1"` ![Android Studio Run Config](https://3739191582-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LF_waG_U-NeI1vhIUwJ%2F-LqnIijeK72sOcRgCDmf%2F-LqnImInlEjOrl_iLAY9%2Fandroid-studio-run-config.png?generation=1570671374625335\&alt=media) `--packageName/-p ` * Android application package name to avoid conflict with the names of classes or interfaces. `iOS` `--bundleId/-b` * iOS Bundle Identifier unique to your app. `--launchArgs` * Arguments to pass to the application when launching it (correspond to the `Arguments Passed On Launch` in application scheme run config in Xcode as can be seen on screenshot below). * Make sure to use `=` on the command line to provide this option, and keep the string in quotes. For example `--launchArgs="-ArgA -ArgB"` `--launchEnvVars` * Environment variables to pass to the application when launching it (correspond to the `Environment Variables` in application scheme run config in Xcode as can be seen on screenshot below). * Make sure to use `=` on the command line to provide this option, and keep the string in quotes. The string should contain `key=value` pairs delimited by spaces. For example `--launchEnvVars="aKey=aValue anotherKey=anotherValue"` * **Default** false ![xcode scheme run](https://3739191582-files.gitbook.io/~/files/v0/b/gitbook-legacy-files/o/assets%2F-LF_waG_U-NeI1vhIUwJ%2F-LqnIijeK72sOcRgCDmf%2F-LqnImIp5JVofvzLQKC5%2Fxcode-scheme-run.png?generation=1570671373653853\&alt=media) **Binary Store Specific Options** `--disableBinaryStore` * Setting this option will bypass retrieval and installation of the binary from the Binary Store. * It can be useful in case you want to use `ern start` command in conjunction with your own mobile application native binary, build locally on your workstation or retrieved from a specific location. `--flavor` * Flavor of the binary to retrieve from the store. * The binary of a specific application version (for ex `1.0.0`) can have different flavors, representing different build types of the same application version (for example `Dev`/`Prod`/`QA` ...). ## Remarks * This command can be used to package multiple MiniApps inside a single composite bundle and automatically start the react-native local packager to serve this bundle. * Use this command when you need to launch and develop or debug your MiniApps from within a native host application which contains other MiniApps along with your MiniApp. * This command works with the `ern link` command. For additional information, see the documentation for the `ern link` command. * When using a binary store, file watcher will be started after the binary is retrieved and installed on the simulator/device. If you are using a binary store and don't want to launch binary from the store, please make sure to use the `--disableBinaryStore` option. Otherwise, file watcher will not be started. ## Related commands [ern link](https://native.electrode.io/v0.47/cli-commands/link) | Link to a MiniApp directory