{
  description = "FatihsMG4 — Android Automotive build environment";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
  };

  outputs = { self, nixpkgs }:
    let
      systems = [ "x86_64-linux" "aarch64-linux" ];
      forAllSystems = f: nixpkgs.lib.genAttrs systems (system: f (import nixpkgs {
        inherit system;
        config = {
          allowUnfree = true;
          android_sdk.accept_license = true;
        };
      }));

      # Must match app/build.gradle (compileSdk 36.1) and EVHardware/lib (compileSdk 36).
      buildToolsVersion = "36.0.0";
    in
    {
      devShells = forAllSystems (pkgs:
        let
          android = pkgs.androidenv.composeAndroidPackages {
            platformVersions = [ "36" "36.1" ];
            buildToolsVersions = [ buildToolsVersion ];
            includeEmulator = false;
            includeNDK = false;
            includeSources = false;
            includeSystemImages = false;
          };
          sdk = "${android.androidsdk}/libexec/android-sdk";
          # gradle/gradle-daemon-jvm.properties pins the daemon to JDK 21.
          jdk = pkgs.jdk21;
        in
        {
          default = pkgs.mkShell {
            packages = [ jdk android.androidsdk ];

            ANDROID_HOME = sdk;
            ANDROID_SDK_ROOT = sdk;
            JAVA_HOME = jdk.home;

            # AGP otherwise downloads an aapt2 binary from Maven, which is dynamically linked
            # against a generic FHS and does not run on NixOS. Use the SDK's patched one.
            # Gradle is also pointed at the Nix JDK so the daemon toolchain criteria are met
            # locally instead of downloading a (non-NixOS) JDK through foojay.
            GRADLE_OPTS = builtins.concatStringsSep " " [
              "-Dorg.gradle.project.android.aapt2FromMavenOverride=${sdk}/build-tools/${buildToolsVersion}/aapt2"
              "-Dorg.gradle.java.installations.paths=${jdk.home}"
              "-Dorg.gradle.java.installations.auto-download=false"
            ];

            shellHook = ''
              echo "sdk.dir=$ANDROID_HOME" > local.properties
              echo "FatihsMG4 dev shell — JDK $(java -version 2>&1 | head -1 | cut -d'"' -f2), SDK at $ANDROID_HOME"
              echo "  ./gradlew assembleStableDebug     # debug APK"
              echo "  ./gradlew assembleUnstableDebug   # build that can update itself (OTA)"
            '';
          };
        });
    };
}