Cannot find native module 'ExpoTaskManager', js engine: hermes

[AhmedMannai10]

Minimal reproducible example

1. Install expo-background-fetch package using npm or yarn. 2. Import and use expo-background-fetch in the project code. 3. Run the project on an Android device or emulator.

Which package manager are you using? (Yarn is recommended)

yarn

If the issue is web-related, please select the bundler (web.bundler in the app.json)

None

Summary

"Cannot find native module 'ExpoTaskManager'" when attempting to use expo-background-fetch package in a React Native project

Environment

expo-env-info 1.2.0 environment info:
System:
OS: Linux 6.5 Ubuntu 22.04.4 LTS 22.04.4 LTS (Jammy Jellyfish)
Shell: 5.8.1 - /usr/bin/zsh
Binaries:
Node: 20.4.0 - /usr/local/bin/node
Yarn: 1.22.22 - /usr/local/bin/yarn
npm: 9.7.2 - /usr/local/bin/npm
SDKs:
Android SDK:
API Levels: 29, 30, 31, 33, 34
Build Tools: 29.0.2, 30.0.3, 33.0.1, 34.0.0
System Images: android-34 | Google APIs Intel x86_64 Atom
npmPackages:
expo: ~50.0.14 => 50.0.14
expo-router: ~3.4.8 => 3.4.8
react: 18.2.0 => 18.2.0
react-dom: 18.2.0 => 18.2.0
react-native: 0.73.6 => 0.73.6
react-native-web: ~0.19.6 => 0.19.10
npmGlobalPackages:
expo-cli: 6.3.10
Expo Workflow: bare

[expo-bot]

Hi there! It looks like your issue requires a minimal reproducible example, but it is invalid or absent. Please prepare such an example and share it in a new issue.

The best way to get attention to your issue is to provide a clean and easy way for a developer to reproduce the issue on their own machine. Please do not provide your entire project, or a project with more code than is necessary to reproduce the issue.

A side benefit of going through the process of narrowing down the minimal amount of code needed to reproduce the issue is that you may get lucky and discover that the bug is due to a mistake in your application code that you can quickly fix on your own.

Resources

• "How to create a Minimal, Reproducible Example"
• "How to narrow down the source of an error"

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[gaisdav]

same error

[AhmedMannai10]

use this package instead
react-native-background-actions

[lachlanwp]

I get the same error in production, but not every time the app is opened. It seems to happen every couple of weeks in two of my apps, both which use expo-background-fetch.

I recently updated the apps to the newer versions. Before doing the update it wouldn't happen. I'd like to stay with Expo if possible! Happy to try to provide more info if required.

Packages and versions in my project:

    "react-native": "0.73.6",
    "expo": "^50.0.0",
    "expo-application": "^5.8.3",
    "expo-background-fetch": "^11.8.1",
    "expo-constants": "^15.4.5",
    "expo-location": "^16.5.5",
    "expo-permissions": "^14.4.0",
    "expo-task-manager": "^11.7.2",

It's been very hard to find steps to reproduce the issue and I've been monitoring it now for at least a month. I've tried lots of different things to try to get it to fire off.

Here's my stack trace:

com.facebook.react.common.JavascriptException: Error: Cannot find native module 'ExpoTaskManager', js engine: hermes, stack:
requireNativeModule@1:1890401
anonymous@1:1896936
loadModuleImplementation@1:79637
guardedLoadModule@1:78871
metroRequire@1:78154
anonymous@1:1894877
loadModuleImplementation@1:79637
guardedLoadModule@1:78871
metroRequire@1:78154
anonymous@1:1883774
loadModuleImplementation@1:79637
guardedLoadModule@1:78871
metroRequire@1:78154
anonymous@1:1880301
loadModuleImplementation@1:79637
guardedLoadModule@1:78871
metroRequire@1:78154
anonymous@1:1241798
loadModuleImplementation@1:79637
guardedLoadModule@1:78871
metroRequire@1:78154
anonymous@1:89607
loadModuleImplementation@1:79637
guardedLoadModule@1:78828
metroRequire@1:78154
global@1:77089

        at com.facebook.react.modules.core.ExceptionsManagerModule.reportException(ExceptionsManagerModule.java:65)
        at java.lang.reflect.Method.invoke(Method.java:-2)
        at com.facebook.react.bridge.JavaMethodWrapper.invoke(JavaMethodWrapper.java:372)
        at com.facebook.react.bridge.JavaModuleWrapper.invoke(JavaModuleWrapper.java:149)
        at com.facebook.jni.NativeRunnable.run(NativeRunnable.java:-2)
        at android.os.Handler.handleCallback(Handler.java:938)
        at android.os.Handler.dispatchMessage(Handler.java:99)
        at com.facebook.react.bridge.queue.MessageQueueThreadHandler.dispatchMessage(MessageQueueThreadHandler.java:29)
        at android.os.Looper.loopOnce(Looper.java:226)
        at android.os.Looper.loop(Looper.java:313)
        at com.facebook.react.bridge.queue.MessageQueueThreadImpl$4.run(MessageQueueThreadImpl.java:234)
        at java.lang.Thread.run(Thread.java:1012)