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Repack app

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Repackage an existing APK, IPA, or .app with an updated JavaScript bundle without a full native rebuild.

For the complete documentation index, see llms.txt. Use this Use this file to discover all available pages.

@expo/repack-app is a CLI tool that repackages an existing Android APK, iOS IPA, or iOS .app bundle without performing a full native build. It updates the existing artifact with a new JavaScript (JS) bundle, assets, and app metadata (such as, app name, version, and package name or bundle identifier). Since there is no native compilation involved, a repack is typically much faster than a full native build.

To learn more about how fingerprint and repack work together to accelerate CI, see Accelerating Continuous Integration with Fingerprint and Repack in EAS Workflows blog post.

Prerequisites

  • An existing build artifact produced from your Expo project: an APK for Android, or an IPA or .app bundle for iOS.
  • (Optional) Signing credentials if the repacked artifact needs to be installable on a device. For more information, see Signing.

When to use repack

Repack assumes the source binary's native side is unchanged since it was built. If you added a native dependency, changed a config plugin, or upgraded the Expo SDK, a repacked artifact will have JS that expects native APIs that do not exist, and will likely crash at runtime. Use fingerprint to compare the source binary's native identity against your current project. If the fingerprints match, then repack is safe. If they differ, do a full native build instead.

Repack is not a replacement for EAS Update. EAS Update ships a new JS bundle to apps that are already installed, and users see it on the next launch. Repack produces a new installable artifact. A good rule of thumb is to use repack for internal testing (QA devices, testers, CI smoke tests) and use EAS Update to deliver JS changes to production users.

Use cases

  • QA cycles: Distribute one base build to testers, then repack with JS fixes for each iteration without waiting for a native rebuild.
  • CI optimization: Build native once per fingerprint, then repack the JS bundle on every subsequent PR to cut wait times from minutes to seconds.
  • Branch testing: Test multiple JS branches against the same native binary to isolate JavaScript-only changes.

Usage

Standalone CLI

You need to run the commands specified for Android and iOS platforms below from your project's root directory. At minimum, --platform and --source-app are required. The tool runs npx expo export:embed under the hood to produce a fresh JS bundle, swaps it into the source binary, and writes the output artifact.

The output format always matches the --source-app input. An APK input produces an APK, an IPA produces an IPA, and a .app bundle produces a .app bundle.

Terminal
- npx @expo/repack-app --platform android --source-app MyApp.apk

Using an IPA:

Terminal
- npx @expo/repack-app --platform ios --source-app MyApp.ipa

Using a .app bundle (for simulator builds, the iOS device artifacts are always IPAs):

Terminal
- npx @expo/repack-app --platform ios --source-app MyApp.app

EAS Workflows

EAS Workflows provides a pre-packaged repack job type that handles signing and build management automatically. See EAS Workflows pre-packaged jobs for full syntax, parameters, and examples.

Signing

To produce an artifact installable on a physical device, pass signing credentials alongside --platform and --source-app. Without them, the Android APK is output unsigned and the iOS IPA cannot be installed on a device. iOS .app bundles intended for the simulator do not need signing and can skip this step.

If you do not already have signing credentials locally, see App credentials for how to obtain a keystore (Android) or a signing identity and provisioning profile (iOS).

Terminal
- npx @expo/repack-app --platform android --source-app MyApp.apk --ks keystore.jks --ks-key-alias my-alias

See the Android-specific options for keystore password flags and other settings.

Pass a signing identity and provisioning profile:

Note: iOS repacking supports ad-hoc and development signing only.

Terminal
- npx @expo/repack-app --platform ios --source-app MyApp.ipa --signing-identity "Apple Distribution: ..." --provisioning-profile /path/to/profile.mobileprovision

See the iOS-specific options for the full list of signing flags.

--js-bundle-only mode

By default, repack updates the JS bundle, assets, and app metadata (app name, version, bundle identifier, and the expo-updates manifest). Pass --js-bundle-only when you intentionally want to update only the JS bundle and leave all native config untouched.

Terminal
- npx @expo/repack-app --platform android --source-app MyApp.apk --js-bundle-only

Limitations

Repack is not recommended for production Google Play Store or Apple App Store submissions. Production builds should go through the complete build pipeline for correct symbolication and signing.

CLI reference

Usage: @expo/repack-app [options] [project-root]

Arguments

ArgumentDescription
[project-root]Path to the project root. Defaults to the current working directory.

Options

OptionDescription
-p, --platform <platform>Required. Platform to repack the app for (android or ios).
--source-app <path>Required. Path to the source app (APK for Android, or IPA or .app for iOS). The output format matches the input.
-o, --output <path>Path to the output artifact. Defaults to repacked.apk, repacked.ipa, or repacked.app in the project root, matching the source format.
-w, --working-directory <path>Path to the working directory for temporary files.
--skip-working-dir-cleanupSkip cleaning up the working directory after the repack completes. Useful for debugging.
-v, --verboseEnable verbose logging.
--js-bundle-onlyOnly update the JS bundle and skip native config updates (such as app name, version, and other metadata).
--embed-bundle-assetsForce running npx expo export:embed to generate the JS bundle and assets, even for debug builds where the bundle is normally loaded from a dev server.
--bundle-assets-sourcemap-output <path>Generate a source map at the specified path. Requires --embed-bundle-assets.

Android-specific options

OptionDescription
--ks <path>Path to the keystore file.
--ks-pass <password>Keystore password. Defaults to pass:android. Supported formats: pass:<password>, env:<name>, file:<file>.
--ks-key-alias <alias>Keystore key alias.
--ks-key-pass <password>Keystore key password. Supported formats: pass:<password>, env:<name>, file:<file>.
--android-build-tools-dir <path>Path to the Android SDK build-tools directory.

iOS-specific options

OptionDescription
--signing-identity <identity>Code signing identity.
--provisioning-profile <path>Path to a provisioning profile. Alternatively, a JSON-encoded value for multi-target apps (for example, when bundling app extensions).