{
  description = "Sample Nix ts-node build";
  inputs = {
    nixpkgs.url = "github:nixos/nixpkgs/nixos-unstable";
    flake-utils.url = "github:numtide/flake-utils";
    gitignore = {
      url = "github:hercules-ci/gitignore.nix";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    android-nixpkgs = {
      url = "github:tadfisher/android-nixpkgs";
    };
  };
  outputs = { self, nixpkgs, flake-utils, gitignore, android-nixpkgs, ... }:
  flake-utils.lib.eachDefaultSystem (system:
  let
    pkgs = import nixpkgs { inherit system; };
    nodejs = pkgs.nodejs-18_x;
    # NOTE: this does not work
    appBuild = pkgs.stdenv.mkDerivation {
      name = "example-ts-node";
      version = "0.1.0";
      src = gitignore.lib.gitignoreSource ./.; # uses the gitignore in the repo to only copy files git would see
      buildInputs = [ nodejs ];
      # https://nixos.org/manual/nixpkgs/stable/#sec-stdenv-phases
      buildPhase = ''
        # each phase has pre/postHooks. When you make your own phase be sure to still call the hooks
        runHook preBuild
        npm ci
        npm run build
        runHook postBuild
      '';
      installPhase = ''
        runHook preInstall
        cp -r node_modules $out/node_modules
        cp package.json $out/package.json
        cp -r dist $out/dist
        runHook postInstall
      '';
    };
    android-sdk = android-nixpkgs.sdk.${system} (sdkPkgs: with sdkPkgs; [
      cmdline-tools-latest
      build-tools-30-0-3
      build-tools-33-0-0
      platform-tools
      platforms-android-33
      emulator
      ndk-23-1-7779620
      cmake-3-22-1
      system-images-android-33-google-apis-x86-64
      system-images-android-34-google-apis-x86-64
    ]);
  in with pkgs; {
    defaultPackage = appBuild;
    devShell = mkShell {
      buildInputs = [ nodejs yarn watchman gradle_7 ];
      ANDROID_SDK_BIN = android-sdk;
      shellHook = ''
        export JAVA_HOME=${pkgs.jdk17.home}
        source ${android-sdk.out}/nix-support/setup-hook
        export PATH=${android-sdk}/bin:$PATH
        ORG_GRADLE_PROJECT_ANDROID_HOME="$ANDROID_HOME"
      '';
    };
  });
}