Install to Claude Code
npx -y skills add https://github.com/hyperb1iss/hyperdroid-skill --skill android-buildDescription
android build
SKILL.md
---
name: android-build
description: Use when building Android apps (Gradle CLI) or ROMs (AOSP, LineageOS). Triggers on "gradle build", "assemble", "AOSP", "LineageOS", "lunch", "mka", "breakfast", "brunch", "compile android", "device tree", "kernel build".
---
# Android Build Systems
This skill covers building Android apps via Gradle CLI and building custom ROMs via AOSP/LineageOS.
---
## App Building (Gradle CLI)
### Essential Commands
```bash
./gradlew tasks # List available tasks
./gradlew assembleDebug # Build debug APK
./gradlew assembleRelease # Build release APK
./gradlew installDebug # Build + install to device
./gradlew bundleRelease # Build AAB (App Bundle)
# APK output location
# app/build/outputs/apk/debug/app-debug.apk
# app/build/outputs/apk/release/app-release.apk
```
### Build Variants
```bash
./gradlew assembleFreeDebug # Flavor + build type
./gradlew assemblePaidRelease
./gradlew assembleDebug --info # Verbose output
./gradlew assembleRelease -x test # Skip tests
```
### Testing
```bash
./gradlew test # Unit tests
./gradlew testDebugUnitTest # Debug unit tests only
./gradlew connectedAndroidTest # Instrumented tests
./gradlew connectedCheck # All connected tests
# Run specific test
./gradlew test --tests "*.MyTestClass"
```
### Linting & Analysis
```bash
./gradlew lint # Run lint
./gradlew lintDebug # Debug only (faster)
./gradlew ktlintCheck # Kotlin style (if configured)
./gradlew detekt # Detekt analysis (if configured)
```
### Clean & Refresh
```bash
./gradlew clean # Clean build
./gradlew clean assembleDebug # Clean + build
./gradlew --refresh-dependencies # Force dependency refresh
./gradlew --stop # Stop Gradle daemon
```
### Dependencies
```bash
./gradlew dependencies # All dependencies
./gradlew app:dependencies # Module dependencies
./gradlew dependencyInsight --dependency <name>
```
### Signing
Debug keystore location:
- Linux: `~/.android/debug.keystore`
- macOS: `~/.android/debug.keystore`
- Windows: `C:\Users\<user>\.android\debug.keystore`
Password: `android`, Alias: `androiddebugkey`
```bash
# Create release keystore
keytool -genkey -v -keystore release.keystore \
-alias my-key-alias -keyalg RSA -keysize 2048 -validity 10000
```
### Performance
```bash
./gradlew assembleDebug --parallel # Parallel builds
./gradlew assembleDebug --build-cache # Use cache
./gradlew assembleDebug --offline # Offline mode
./gradlew --scan # Build scan (uploads data)
./gradlew --profile # Local profile report
```
### gradle.properties Optimization
```properties
org.gradle.jvmargs=-Xmx4g -XX:+HeapDumpOnOutOfMemoryError
org.gradle.parallel=true
org.gradle.caching=true
org.gradle.configuration-cache=true
android.useAndroidX=true
```
---
## SDK Management
### sdkmanager
```bash
sdkmanager --list # List available packages
sdkmanager --list | grep system # Filter system images
sdkmanager "platform-tools" # Install package
sdkmanager "platforms;android-34" # Install platform
sdkmanager "system-images;android-34;google_apis;x86_64"
sdkmanager --update # Update all
sdkmanager --licenses # Accept licenses
```
### avdmanager
```bash
avdmanager list device # List device profiles
avdmanager list avd # List created AVDs
# Create AVD
avdmanager create avd -n my_avd \
-k "system-images;android-34;google_apis;x86_64" \
-d pixel_6
avdmanager delete avd -n my_avd
```
### Emulator CLI
```bash
emulator -list-avds # List AVDs
emulator @my_avd # Start AVD
emulator @my_avd -no-snapshot # Fresh boot
emulator @my_avd -no-window # Headless
emulator @my_avd -wipe-data # Factory reset
```
---
## ROM Building (AOSP/LineageOS)
### Environment Setup
```bash
# Install repo tool
mkdir -p ~/.bin
curl https://storage.googleapis.com/git-repo-downloads/repo > ~/.bin/repo
chmod a+x ~/.bin/repo
export PATH="$HOME/.bin:$PATH"
# Initialize repo
mkdir android && cd android
repo init -u https://github.com/LineageOS/android.git -b lineage-21.0
# Or AOSP: repo init -u https://android.googlesource.com/platform/manifest
# Sync source
repo sync -c -j$(nproc) --force-sync --no-tags --no-clone-bundle
```
### Build Commands
```bash
# Setup environment
source build/envsetup.sh
# Select device
lunch <device>-userdebug # AOSP
breakfast <device> # LineageOS
# Build
m # Full build
mka bacon # LineageOS (with flashable zip)
mka bootimage # Just boot.img
mka systemimage # Just system
# Parallel build
m -j$(nproc)
```
### Build Variants
| Variant | Purpose |
| ----------- | -------------------------------------- |
| `user` | Production, no root, limited debugging |
| `userdebug` | Like user + root + debugging |
| `eng` | Development, all debug tools |
### Common Targets
```bash
m bootimage # Kernel + ramdisk
m systemimage # System partition
m vendorimage # Vendor partition
m otapackage # OTA zip
mka bacon # LineageOS flashable zip
# Module-specific
m Settings # Just Settings app
mm # Build current directory
mmm packages/apps/Settings # Build specific path
```
### LineageOS Specifics
```bash
breakfast <device> # Setup + sync device deps
brunch <device> # breakfast + mka bacon
# Cherry-pick from Gerrit
repopick <change_number>
repopick -t <topic>
# Sync specific project
repo sync packages/apps/Settings
```
### Build Output
```
out/target/product/<device>/
├── boot.img # Kernel + ramdisk
├── system.img # System partition
├── vendor.img # Vendor partition
├── lineage-*.zip # Flashable zip (LineageOS)
└── recovery.img # Recovery (non-A/B)
```
---
## Device Trees
### Structure
```
device/<vendor>/<device>/
├── AndroidProducts.mk # Product makefiles list
├── BoardConfig.mk # Board configuration
├── device.mk # Device makefile
├── lineage_<device>.mk # LineageOS product
├── extract-files.sh # Vendor blob extraction
├── proprietary-files.txt # Blob list
├── sepolicy/ # SELinux policies
└── overlay/ # Resource overlays
```
### Key Files
**BoardConfig.mk** - Hardware configuration:
```makefile
TARGET_ARCH := arm64
TARGET_BOARD_PLATFORM := <platform>
TARGET_BOOTLOADER_BOARD_NAME := <device>
BOARD_KERNEL_CMDLINE := ...
BOARD_BOOT_HEADER_VERSION := 4
```
**device.mk** - Device packages:
```makefile
PRODUCT_PACKAGES += \
android.hardware.audio@7.0-impl \
audio.primary.$(TARGET_BOARD_PLATFORM)
PRODUCT_COPY_FILES += \
$(LOCAL_PATH)/configs/audio_policy.conf:...
```
---
## Kernel Building
### Standalone
```bash
# Setup
export ARCH=arm64
export CROSS_COMPILE=aarch64-linux-gnu-
# Or for Clang:
export CC=clang
export CLANG_TRIPLE=aarch64-linux-gnu-
# Configure
make <device>_defconfig
# Build
make -j$(nproc)
# Output
arch/arm64/boot/Image.gz
```
### In AOSP Tree
```makefile
# In BoardConfig.mk
TARGET_KERNEL_SOURCE := kernel/<vendor>/<device>
TARGET_KERNEL_CONFIG := <device>_defconfig
TARGET_KERNEL_CLANG_COMPILE := true
```
---
## Troubleshooting
### Common Gradle Issues
```bash
# OOM
export GRADLE_OPTS="-Xmx4g"
# Daemon issues
./gradlew --stop
rm -rf ~/.gradle/daemon
# Cache issues
./gradlew clean --refresh-dependencies
```
### Common AOSP Issues
```bash
# Ninja error - usually dependency issue
m clean && m
# Jack server (old builds)
./prebuilts/sdk/tools/jack-admin kill-server
./prebuilts/sdk/tools/jack-admin start-server
# SELinux issues
audit2allow -i audit.log
```
### Build Logs
```bash
# Gradle
./gradlew assembleDebug --stacktrace
./gradlew assembleDebug --info
# AOSP
m 2>&1 | tee build.log
```
---
## Quick Reference
### Gradle
| Task | Command |
| ------------- | --------------------------- |
| Build debug | `./gradlew assembleDebug` |
| Build release | `./gradlew assembleRelease` |
| Install | `./gradlew installDebug` |
| Test | `./gradlew test` |
| Lint | `./gradlew lint` |
| Clean | `./gradlew clean` |
| Dependencies | `./gradlew dependencies` |
### AOSP/LineageOS
| Task | Command |
| ------------- | -------------------------- |
| Setup env | `source build/envsetup.sh` |
| Select device | `lunch <device>-userdebug` |
| Full build | `m` |
| LineageOS zip | `mka bacon` |
| Just boot | `mka bootimage` |
| Sync | `repo sync -c -j$(nproc)` |