Configure Android environmentsAndroid

Last updated 2026-10-07

The android block of fastlane/config/environments.yml defines how each environment is built and where it is distributed. You can generate it with fastlane init_project or write it by hand.

fastlane/config/environments.yml

android:
  enabled: true
  project_dir: "android"
  use_flavors: false            # true when build.gradle defines productFlavors
  build:
    clean_before_build: false   # run `gradle clean` first
    gradle_options: ""          # e.g. "--no-daemon --stacktrace"
  environments:
    development:
      gradle_task: "assembleRelease"   # ★ source of truth – exact Gradle task
      artifact:
        type: "APK"                    # APK or AAB
        glob: "android/app/build/outputs/apk/release/*.apk"
      firebase:
        enabled: true
        app_id: "${FIREBASE_ANDROID_DEV_APP_ID}"   # empty → read from google-services.json
        groups: "${FIREBASE_ANDROID_DEV_GROUPS}"   # tester group aliases, comma-separated
        testers: ""                                # or tester e-mails, comma-separated
      app_testing:
        enabled: true                  # AI tests for this environment
      release_notes: { enabled: true, source: "git", commit_count: 10 }
      notifications: { teams: { enabled: true }, slack: { enabled: false } }

Key reference

Key	Required	Description
`gradle_task`	Yes	Exact Gradle task to run. The framework never guesses this: it is the source of truth.
`artifact.type`	Yes	`APK` or `AAB`. Passed to Firebase as `android_artifact_type`.
`artifact.glob`	Yes	Glob, relative to the project root, that matches the file Gradle produces.
`flavor / build_type`	No	Informational (shown by `doctor`/`info`), and used by the interactive setup.
`firebase.app_id`	When enabled	Firebase App ID (`1:123…:android:abc…`). Detected from `google-services.json` when empty.
`firebase.groups / testers`	One of them	Group aliases or e-mail addresses, comma-separated.
`app_testing.enabled`	No	Runs the App Testing agent after upload (APK only).

No-flavor project

If Gradle only exposes assembleDebug, assembleRelease and bundleRelease, keep use_flavors: false and set gradle_task: "assembleRelease".

Note: in that case development, staging and production can all ship the same Release APK, and only the Firebase destination or group differs. That is intentional. For truly isolated environments (separate app IDs and backends), add product flavors.

Flavor project

If android/app/build.gradle defines product flavors, Gradle creates one task per flavor and build type combination:

android/app/build.gradle

android {
    flavorDimensions "env"
    productFlavors {
        dev     { dimension "env"; applicationIdSuffix ".dev" }
        staging { dimension "env"; applicationIdSuffix ".staging" }
        prod    { dimension "env" }
    }
}

Set use_flavors: true and configure each environment with the matching task:

YAML

staging:
  flavor: "staging"
  build_type: "release"
  gradle_task: "assembleStagingRelease"
  artifact:
    type: "APK"
    glob: "android/app/build/outputs/apk/staging/release/*.apk"

The explicit gradle_task always wins. To see every task your project actually has, ask Gradle:

my-app/android — zsh

~/my-app $ ./gradlew tasks --all | grep -E "^(assemble|bundle).*Release "
assembleDevRelease - Assembles main output for variant devRelease
assembleProdRelease - Assembles main output for variant prodRelease
assembleStagingRelease - Assembles main output for variant stagingRelease
bundleDevRelease - Assembles bundle for variant devRelease
bundleProdRelease - Assembles bundle for variant prodRelease
bundleStagingRelease - Assembles bundle for variant stagingRelease

On Windows use .\gradlew.bat tasks --all | Select-String Release.

Common Gradle task / glob combinations

Project type	gradle_task	artifact.glob
No flavors, APK	`assembleRelease`	`android/app/build/outputs/apk/release/*.apk`
No flavors, AAB	`bundleRelease`	`android/app/build/outputs/bundle/release/*.aab`
Flavor dev, APK	`assembleDevRelease`	`android/app/build/outputs/apk/dev/release/*.apk`
Flavor prod, AAB	`bundleProdRelease`	`android/app/build/outputs/bundle/prodRelease/*.aab`
Custom variant	e.g. `assembleInternalQaRelease`	matching output folder

APK or AAB?

	APK	AAB
Install directly from Firebase	Yes	Only if the Firebase project is linked to Google Play
App Testing agent (AI tests)	Yes	No
Google Play upload	Legacy only	Required format (About App Bundles)

Tip: doctor checks that the task really exists (gradlew tasks --all) before a long build starts.

Next steps

Set up Firebase App DistributionRegister the app and testers.Learn more

Official documentation

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