PhaseScriptExecution failed for react-native-config on Xcode build

Usually this problem when a dependency is not updated.

You can try the following steps:

1-) cd ios
2-) rm -rf Podfile.lock
3-) rm -rf Pods
4-) delete .xcworkspace
5-) pod install

I had the same Problem, I followed a tutorial to build ios, it is pretty old (one year) in tutorial I added code which include some thing like

post_install do |installer|
installer.pods_project.targets.each do |target|
  if target.name == 'React'
  target.remove_from_project
  end
  if target.name == 'react-native-config'
    phase = target.project.new(Xcodeproj::Project::Object::PBXShellScriptBuildPhase)
    phase.shell_script = 'cd ../../'\
    '&& RNC_ROOT=./node_modules/react-native-config/'\
    '&& export SYMROOT=$RNC_ROOT/ios/ReactNativeConfig'\
    '&& export BUILD_DIR=$RNC_ROOT/ios/ReactNativeConfig'\
    '&& ruby $RNC_ROOT/ios/ReactNativeConfig/BuildDotenvConfig.ruby'
    target.build_phases << phase
    target.build_phases.move(phase,0)
  end
 end
end

please delete it from podfile and follow the doc of react-native-config to use environment variables here after delete dont forget pod install

while building take care of build scheme (which one are you using while build time)

If anyone is facing this issue while using rbenv, please ensure that ruby is installed locally in project folder.

Occur due to some mismatch of packages, search for a package which shows the error and remove the package

After that

delete ios folder install react native eject package

npm i react-native-eject

re-create ios folder

npx react-native eject

install pod

cd ios
pod install

For me, I used ts-node to run some typescript code in the Run Script phase, the ts-node executable was not in /usr/local/bin/ts-node which caused the build to fail.

Try to run the code inside the Run Script editor directly in the terminal, that might give you a clue about why the build fails.