June 2025 monthly summary focusing on build reliability, packaging robustness, and deployment flexibility across two Mozilla repositories. Key outcomes include non-destructive handling of NDK environment variables, explicit Python3 usage to ensure consistent builds, and improved packaging/setup tooling for macOS and Android environments. These changes reduce build failures, improve cross-platform consistency, and accelerate developer onboarding. Provided highlights by repository: - mozilla/application-services: - Respect pre-configured NDK paths: prevents overwriting existing ANDROID_NDK_HOME and ANDROID_NDK_ROOT; if set, existing values are preserved, ensuring a stable build environment. Commit: 9a8ed6d9cec2b6d56ac1c61bf363337f7faa51ca (Do not overwrite NDK related variables). - Explicitly use Python3 across build scripts: standardizes to python3 to avoid environment issues across Android, desktop, and iOS NSS builds. Commit: fc23aec5784e8b4fb8155b6a16cf489af49d6594 (Always use python3 and not python). - mozilla/gecko-dev: - macOS DMG Packaging Robustness: adds pre-bootstrap checks for tool existence via buildconfig.substs before bootstrap_toolchain, reducing DMG packaging failures. Commit: df7bd504ce200576b408c5c89a29e27e7aa83ddf (Bug 1971306 - Check if MacOS packaging tools exist before bootstraping). - Android SDK Setup: Configurable Paths and Optional AVD Download: introduces ANDROID_BUNDLETOOL_PATH and ANDROID_AVD_PATH for custom locations; makes AVD download optional during the check phase, increasing setup flexibility. Commit: 61f23a8ddd7695fb6790c96860d5ba6ae220a610 (Bug 1972755 - Add options to change location of bundletool and avd).