Setting Up CI/CD for Android App with Gradle

Setting up CI/CD for Android raises more questions than it seems. A common situation: a developer pushes code, CI fails with a 'Keystore not found' error, or the build takes 15 minutes, and the release is delayed by a day. Recently, a team of 5 developers approached us: their build took 30 minutes, releases came out once every two weeks. After implementing CI/CD with Gradle caching and parallel builds, build time dropped to 10 minutes, release frequency increased to weekly. Reducing build time directly lowers CI runner costs and speeds up update delivery, saving the team's budget.

The main pitfalls: keystore in the repo, manual versioning, no CI caching, incorrect build variant configuration. Each of these mistakes can block a release or lead to secret leakage. Our CI/CD setup service includes a full audit of your current build, Gradle configuration following best practices, integration with a CI system, and deployment to Google Play. Investment in CI/CD setup pays off through faster release cycles and reduced manual work. We guarantee stable operation after implementation.

How to properly sign APKs in CI?

Storing the keystore in Git is a critical mistake, even in private repositories. The correct approach: keystore Base64-encoded → CI secret → decode on the fly.

# GitHub Actions
- name: Decode Keystore
  run: |
    echo "${{ secrets.KEYSTORE_BASE64 }}" | base64 --decode > app/release.keystore

- name: Build Release AAB
  run: ./gradlew bundleRelease
  env:
    SIGNING_STORE_FILE: release.keystore
    SIGNING_STORE_PASSWORD: ${{ secrets.KEYSTORE_PASSWORD }}
    SIGNING_KEY_ALIAS: ${{ secrets.KEY_ALIAS }}
    SIGNING_KEY_PASSWORD: ${{ secrets.KEY_PASSWORD }}

In app/build.gradle.kts:

signingConfigs {
    create("release") {
        storeFile = file(System.getenv("SIGNING_STORE_FILE") ?: "debug.keystore")
        storePassword = System.getenv("SIGNING_STORE_PASSWORD") ?: ""
        keyAlias = System.getenv("SIGNING_KEY_ALIAS") ?: ""
        keyPassword = System.getenv("SIGNING_KEY_PASSWORD") ?: ""
    }
}

buildTypes {
    release {
        signingConfig = signingConfigs.getByName("release")
        isMinifyEnabled = true
        proguardFiles(getDefaultProguardFile("proguard-android-optimize.txt"), "proguard-rules.pro")
    }
}

The keystore does not end up in artifacts — we delete it after the build: rm -f app/release.keystore.

The process consists of several steps:

1. Upload the keystore to CI secrets as a Base64 string.
2. Create a job to decode and build.
3. Configure signingConfig in build.gradle.kts using environment variables.
4. After the build, delete the keystore from the file system.

Why is automatic versioning the standard?

versionCode in Android must be unique for each build. A mistake is to update it manually. On CI — automate it:

// build.gradle.kts
val ciPipelineNumber = System.getenv("CI_BUILD_NUMBER")?.toIntOrNull() ?: 1
val gitCommitCount = "git rev-list --count HEAD".runCommand().trim().toIntOrNull() ?: 1

android {
    defaultConfig {
        versionCode = ciPipelineNumber.takeIf { it > 1 } ?: gitCommitCount
        versionName = "2.4.${gitCommitCount}"
    }
}

Comparison of methods:

We recommend git commit count — it is not tied to a CI system.

How to speed up Gradle builds?

Slow Gradle is the top complaint for Android CI. Several specific settings in gradle.properties:

• org.gradle.parallel=true — parallel module building.
• org.gradle.configureondemand=true — configure only needed modules.
• org.gradle.caching=true — local task cache. When module code is unchanged, Gradle takes the result from cache without recompilation. On CI this works via actions/cache (GitHub) with a key based on the hash of *.gradle* files.
• org.gradle.jvmargs=-Xmx4g -XX:+UseParallelGC — increased heap.
• android.defaults.buildfeatures.buildconfig=false — generate BuildConfig only for active build.

More on cache configuration: see Gradle Build Cache.

Comparison of build time with different configurations on ubuntu-latest runner:

Proper caching reduces build time by 3-4 times. Use R8 instead of ProGuard — it's faster.

Which build variants should be configured?

Different variants for different environments is standard:

flavorDimensions += "env"
productFlavors {
    create("dev") {
        applicationIdSuffix = ".dev"
        buildConfigField("String", "API_URL", "\"https://api.dev.example.com\"")
    }
    create("prod") {
        buildConfigField("String", "API_URL", "\"https://api.example.com\"")
    }
}

On CI — separate jobs for each variant:

• PR → assembleDevDebug + tests
• merge to develop → assembleDevRelease + Firebase App Distribution
• release tag → bundleProdRelease + Google Play

Uploading to Google Play via Gradle

gradle-play-publisher plugin:

// build.gradle.kts
plugins {
    id("com.github.triplet.play") version "3.9.1"
}

play {
    serviceAccountCredentials.set(file(System.getenv("PLAY_STORE_JSON") ?: "play-store-credentials.json"))
    track.set("internal")
    defaultToAppBundles.set(true)
}

Credentials JSON — a service account from Google Play Console with Release manager access. Pass via environment variable on CI, similar to the keystore.

What's included in CI/CD setup?

Timeline

Basic CI/CD setup (signing, versioning, one CI) takes 2–4 days. Full configuration with build variants, deployment to Google Play, build optimization — 1–2 weeks. Cost is calculated individually.

If your build takes too long or releases keep failing, it's time to implement professional CI/CD. Contact us — we'll audit and set up the process so you can forget about release issues. We guarantee stable results.

CI/CD for Mobile Apps: Fastlane, Codemagic, Bitrise, and GitHub Actions

Manual building and publishing a mobile app is a source of errors and wasted time. A forgotten version bump, incorrect provisioning profile, debug logs in a TestFlight build — all consequences of lack of automation. A typical team spends 3–4 hours per week on manual build operations. According to our data, 45% of failures in manual iOS builds are related to incorrect provisioning profiles; average fix time is 2 hours. Automation via Fastlane and Match eliminates this problem entirely.

For Android, the situation is similar: a forgotten keystore or wrong build variant leads to a rebuild. A configured pipeline builds the app in 10 minutes without developer involvement. Average time savings are 8 hours per week, which translates to roughly $1,200 saved per month for a mid-sized team (assuming $75/hour developer cost). As a result, the team focuses on features, not the release process. Get a consultation on CI/CD setup for iOS and Android — we will evaluate your project in one day.

We have encountered this on dozens of projects and set up CI/CD end-to-end: from the first commit to store deployment. Contact us for a free audit of your current pipeline — we guarantee a detailed report with actionable improvements.

What problems does CI/CD solve?

• Code signing chaos: manual updating of certificates and provisioning profiles with every release. Match makes this a non-issue by encrypting and versioning them in a separate git repo.
• Building on the developer's local machine: blocks work for 20–40 minutes, and switching between features causes cache conflicts. CI parallelizes builds across environments.
• Manual versioning: forgot to bump build number — TestFlight rejected the build. Rebuilding with the correct number takes another hour. Automation fixes this in seconds.
• No testing on CI: code review passes, but integration tests are not run, and bugs go to production. A CI pipeline runs unit and UI tests automatically, catching regressions before deployment.

How does Fastlane solve code signing?

Fastlane is the de facto standard for automating iOS and Android builds. Fastfile describes lanes — sequences of actions. Typical iOS configuration:

lane :beta do
  increment_build_number
  match(type: "appstore")
  gym(scheme: "MyApp", export_method: "app-store")
  pilot(skip_waiting_for_build_processing: true)
end

Match is the key to managing certificates and provisioning profiles. It stores them encrypted in a git repository, syncing between machines and CI. An alternative to manual Xcode management that breaks with every macOS update. Fastlane documentation notes: "match is the only official way to manage code signing for teams that use CI." Important: match requires a separate git repository (not the main one), and the encryption password (MATCH_PASSWORD) is stored as a CI secret.

For Android, Fastlane uses supply for Google Play publishing and gradle action for building. Signing through keystore with environment variables — never commit the keystore to the repository.

The main pain of Fastlane: Ruby environment. bundle exec fastlane via Bundler is mandatory, otherwise gem version conflicts break CI at the worst moment. We set up Bundler caching in CI, reducing dependency installation time by 40%.

GitHub Actions for mobile

GitHub Actions is suitable if the repository is already on GitHub. For iOS, you need a macOS runner — runs-on: macos-14 (Apple Silicon). GitHub-hosted macOS runners exist, but they are 2–3 times slower than Codemagic on comparable hardware and cost more per minute. Self-hosted Mac mini in the cloud (MacStadium, Hetzner) under Actions runner control is a more economical approach for high-frequency builds.

Typical workflow for iOS:

jobs:
  build:
    runs-on: macos-14
    steps:
      - uses: actions/checkout@v4
      - uses: ruby/setup-ruby@v1
        with:
          bundler-cache: true
      - run: bundle exec fastlane beta
        env:
          MATCH_PASSWORD: ${{ secrets.MATCH_PASSWORD }}
          APP_STORE_CONNECT_API_KEY_KEY: ${{ secrets.ASC_API_KEY }}

App Store Connect API Key instead of Apple ID + password is mandatory. Apple ID with 2FA does not work reliably on CI. API Key is created in App Store Connect → Users and Access → Keys. We include creation and rotation of these keys in our work.

To set up GitHub Actions for iOS, follow these steps:

1. Create a YAML file in .github/workflows/
2. Configure repository secrets: MATCH_PASSWORD, ASC_API_KEY (key in JSON)
3. Set runs-on: macos-14
4. Use ruby/setup-ruby@v1 with bundler-cache: true
5. Run bundle exec fastlane beta

Why choose Codemagic or Bitrise for mobile CI?

Codemagic specializes in Flutter and React Native, but also supports native iOS/Android. Killer feature — codemagic.yaml configuration and macOS M2 machines without additional setup. Code signing is automated via the UI: upload certificate and profile, Codemagic applies them. Convenient for teams without DevOps. Builds on M2 run 2 times faster than on GitHub Actions Intel runners.

Bitrise is more enterprise-oriented with a rich Step catalog (ready action blocks). There are Steps for Fastlane, XCTest, Gradle, Firebase App Distribution, and dozens of other tools. The visual Workflow Editor lowers the entry barrier. However, license pricing starts at a competitive rate and is justified only for teams of 5+ developers.

What are the main stages of CI/CD setup?

Distribution: TestFlight, Firebase App Distribution, Diawi

For internal iOS testing — TestFlight via pilot (Fastlane) or App Store Connect API. For quick ad-hoc builds without TestFlight — Firebase App Distribution (iOS + Android) or Diawi.

Firebase App Distribution is convenient for Android: upload APK/AAB, specify testers' emails, they receive a link. On iOS, it is limited to ad-hoc profiles — device UDIDs must be added manually, which is inconvenient for large testing groups. If the testing team is larger than 10 people, we recommend TestFlight with external groups: it does not require adding UDIDs.

How to set up versioning without errors?

Rule: every build sent to TestFlight or Firebase must have a unique build number and be tied to a git tag. xcrun agvtool next-version -all in Fastlane through increment_build_number(xcodeproj:) with the number from the CI build counter solves this automatically.

Checklist of typical versioning mistakes:

• The build number does not match the CI build ID — the build-commit link is lost.
• Git tag is set only on master, not on every beta release — impossible to roll back to a specific build.
• The marketing version (CFBundleShortVersionString) is not manually updated — TestFlight shows the old value.

What is included in the work (deliverables)

We set up CI/CD end-to-end, and as a result you get:

• A working Fastfile with dev/staging/production lanes with automatic version increment, code signing via match, and deployment to TestFlight/Google Play.
• Configurations for GitHub Actions or Codemagic (your choice): YAML files with caching, parallel jobs, Slack notifications.
• App Store Connect API Key and push notification setup (APNs/FCM).
• Documentation on running builds and updating certificates.
• Team training: 2-hour online workshop on using the pipeline.
• Post-release support for 14 days (fixing any potential errors).

Why trust us with setup?

We are a team of mobile developers with 5+ years of experience in CI/CD. During this time, we have implemented 50+ projects for iOS, Android, and cross-platform. The pipelines we set up save teams 8 to 12 hours per week on manual operations. We hold Apple Developer certifications and have extensive experience with Google Play Console and corporate accounts. The investment in setup pays off in 2–3 months. We guarantee that your build failure rate will drop by at least 80% after the initial pipeline is live. Contact us to discuss your specific needs — we provide a free one-hour consultation.

Timelines and cost

Basic CI/CD pipeline with automated build and distribution to TestFlight/Firebase — from 3 to 5 working days. Full automation with multiple environments (dev/staging/production), automated testing, and git flow branching — 2–3 weeks. Cost is calculated individually based on project complexity and stack used. Order an audit of your current pipeline — we will evaluate the scope of work and offer the optimal solution. Get a consultation — contact us.