Expo Docs MCP Server

--- title: Install Expo modules in an existing React Native project sidebar_title: Install Expo modules description: Learn how to prepare your existing React Native project to install and use any Expo module. --- To use Expo modules in your app, you will need to install and configure the `expo` package. The `expo` package has a small footprint; it includes only a minimal set of packages that are needed in nearly every app and the module and autolinking infrastructure that other Expo SDK packages are built with. Once the `expo` package is installed and configured in your project, you can use `npx expo install` to add any other Expo module from the SDK. Depending on how you [initialized the project](/bare/overview/), there are two ways you can install the Expo modules: [automatically](#automatic-installation) or [manually](#manual-installation). ## Automatic installation To install and use Expo modules, the easiest way to get up and running is with the `install-expo-modules` command. - **When the command succeeds**, you will be able to add any Expo module in your app! Proceed to [Usage](#usage) for more information. - **If the command fails**, follow the manual installation instructions. Updating code programmatically can be tricky, and if your project deviates significantly from a default React Native project, then you need to perform manual installation and adapt the instructions here to your codebase. ## Manual installation The following instructions apply to installing the latest version of Expo modules in React Native 0.79. For previous versions, check the [native upgrade helper](/bare/upgrade) to see how these files are customized. Once installation is complete, apply the changes from the following diffs to configure Expo modules in your project. This is expected to take about five minutes, and you may need to adapt it slightly depending on how customized your project is. ### Configuration for Android ### Configuration for iOS Optionally, you can also add additional delegate methods to your **AppDelegate.swift**. Some libraries may require them, so unless you have a good reason to leave them out, it is recommended to add them. [See delegate methods in AppDelegate.swift](https://github.com/expo/expo/blob/sdk-53/templates/expo-template-bare-minimum/ios/HelloWorld/AppDelegate.swift#L24-L42). Save all of your changes and update your iOS Deployment Target in Xcode to `iOS 15.1`: - Open **your-project-name.xcworkspace** in Xcode, select your project in the left sidebar. - Select **Targets** > **your-project-name** > **Build Settings** > **iOS Deployment Target** and set it to `iOS 15.1`. The last step is to install the project's CocoaPods again to pull in Expo modules that are detected by `use_expo_modules!` directive that we added to the **Podfile**: ### Configure Expo CLI for bundling on Android and iOS We recommend using Expo CLI and related tooling configurations to bundle your app JavaScript code and assets. This adds support for using the `"main"` field in **package.json** to use [Expo Router](/router/introduction/) library. Not using Expo CLI for bundling may result in unexpected behavior. [Learn more about Expo CLI](/bare/using-expo-cli/). Replace the shell script under **Build Phases** > **Bundle React Native code and images** in Xcode with the following: ```sh /bin/sh if [[ -f "$PODS_ROOT/../.xcode.env" ]]; then source "$PODS_ROOT/../.xcode.env" fi if [[ -f "$PODS_ROOT/../.xcode.env.local" ]]; then source "$PODS_ROOT/../.xcode.env.local" fi # The project root by default is one level up from the ios directory if [[ "$CONFIGURATION" = *Debug* ]]; then export SKIP_BUNDLING=1 fi if [[ -z "$ENTRY_FILE" ]]; then # Set the entry JS file using the bundler's entry resolution. export ENTRY_FILE="$("$NODE_BINARY" -e "require('expo/scripts/resolveAppEntry')" "$PROJECT_ROOT" ios relative | tail -n 1)" fi if [[ -z "$CLI_PATH" ]]; then # Use Expo CLI export CLI_PATH="$("$NODE_BINARY" --print "require.resolve('@expo/cli')")" fi if [[ -z "$BUNDLE_COMMAND" ]]; then # Default Expo CLI command for bundling export BUNDLE_COMMAND="export:embed" fi `"$NODE_BINARY" --print "require('path').dirname(require.resolve('react-native/package.json')) + '/scripts/react-native-xcode.sh'"` ``` And add support the `"main"` field in **package.json** by making the following change to **AppDelegate.swift**: ```diff AppDelegate.swift override func bundleURL() -> URL? { #if DEBUG - RCTBundleURLProvider.sharedSettings().jsBundleURL(forBundleRoot: "index") + RCTBundleURLProvider.sharedSettings().jsBundleURL(forBundleRoot: ".expo/.virtual-metro-entry") #else Bundle.main.url(forResource: "main", withExtension: "jsbundle") #endif ``` ## Usage ### Verifying installation You can verify that the installation was successful by logging a value from [`expo-constants`](/versions/latest/sdk/constants). - Run `npx expo install expo-constants` - Then, run `npx expo run` and modify your app JavaScript code to add the following: ```js console.log(Constants.systemFonts); ``` ### Using Expo SDK packages Once the `expo` package is installed and configured in your project, you can use `npx expo install` to add any other Expo module from the SDK. See [Using Libraries](/workflow/using-libraries) for more information. ### Expo modules included in the `expo` package The following Expo modules are brought in as dependencies of the `expo` package: - [`expo-application`](/versions/latest/sdk/application) - Generates the installation id in remote logging in development. This module is optional and can be safely removed if you do not use `expo-dev-client`. - [`expo-asset`](/versions/latest/sdk/asset) - A JavaScript-only package that builds around `expo-file-system` and provides a common foundation for assets across all Expo modules. - [`expo-constants`](/versions/latest/sdk/constants) - Provides access to the manifest. - [`expo-file-system`](/versions/latest/sdk/filesystem) - Interact with the device file system. Used by `expo-asset` and many other Expo modules. Commonly used directly by developers in application code. - [`expo-font`](/versions/latest/sdk/font) - Load fonts at runtime. This module is optional and can be safely removed, however; it is recommended if you use `expo-dev-client` for development and it is required by `@expo/vector-icons`. - [`expo-keep-awake`](/versions/latest/sdk/keep-awake) - Prevents your device from going to sleep while developing your app. This module is optional and can be safely removed. To exclude any of these modules, refer to the following guide on [excluding modules from autolinking](#excluding-specific-modules-from-autolinking). ### Excluding specific modules from autolinking If you need to exclude native code from Expo modules you are not using, but were installed by other dependencies, you can use the [`expo.autolinking.exclude`](/modules/autolinking/#exclude) property in **package.json**: ```json package.json { "name": "...", "dependencies": {}, "expo": { "autolinking": { "exclude": ["expo-keep-awake"] } } } ```