What is EAS Build, and how does it differ from building locally on a developer's machine?

Short answer

EAS Build is an integrated cloud service that runs dedicated macOS and Linux servers equipped with Xcode and Android SDK to create APK, AAB, and IPA files without using the developer's device power and disk space.

Explanation

Building iOS apps locally requires a recent Mac, a 40 GB Xcode download, and maintenance of signing certificates. EAS Build lets any developer, including those on Windows or Linux, build signed production packages for app stores with one click in the cloud, with secure management of certificates and environments.

Code example

// eas.json file for configuring build profiles:
{
  "build": {
    "development": {
      "developmentClient": true,
      "distribution": "internal"
    },
    "preview": {
      "distribution": "internal"
    },
    "production": {
      "autoIncrement": true
    }
  }
}

Common mistakes

• Believing that EAS Build requires publishing app code publicly or does not support manually configured Bare projects.

Follow-up questions

• What are Over-The-Air (OTA) updates through EAS Update, and what are their risks?
• How do you manage environment variables safely and reliably in Expo?

Sources

• Expo docs — EAS Build introduction