Learn how to run EAS Build on your own custom infrastructure.

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You can run the same build process that we run on the EAS Build servers directly on your machine with the --local flag.

Note: if you use Continuous Native Generation, you can run prebuild to generate your android and ios directories and then proceed open the projects in the respective IDEs and build them just like any native project. It's not necessary to run eas build --local, but it handles more of the build process for you — see "Use cases for local builds".

Prerequisites

You need to be authenticated with Expo:

• Run eas login,
• or set EXPO_TOKEN (learn more about token-based authentication).

Use cases for local builds

• Company policies that restrict the use of third-party CI/CD services. With local builds, the entire process runs on your infrastructure and the only communication with EAS servers is:
  • to make sure project @account/slug exists
  • if you are using managed credentials to download them.
• Debugging build failures on EAS servers.

Using local builds for debugging

If you encounter build failures on EAS servers and you're unable to determine the cause from inspecting the logs, you may find it helpful to debug the issue locally. To simplify that process we support a number of environment variables to configure the local build process.

• EAS_LOCAL_BUILD_SKIP_CLEANUP=1 - Set this to disable cleaning up the working directory after the build process is finished.
• EAS_LOCAL_BUILD_WORKINGDIR - Specify the working directory for the build process, by default it's somewhere (it's platform dependent) in /tmp folder.
• EAS_LOCAL_BUILD_ARTIFACTS_DIR - The directory where artifacts are copied after a successful build. By default these files are copied to the current directory, which may be undesirable if you are running many consecutive builds.

Limitations

Some of the options available for cloud builds are not available locally. Limitations you should be aware of:

• You can only build for a specific platform (option all is disabled).
• Customizing versions of software is not supported, fields node, yarn, fastlane, cocoapods, ndk, image in eas.json are ignored.
• Caching is not supported.
• EAS Secrets are not supported (set them in your environment locally instead).
• You are responsible for making sure that the environment has all the necessary tools installed:
  • Node.js/yarn/npm
  • fastlane (iOS only)
  • CocoaPods (iOS only)
  • Android SDK and NDK