{
  lib,
  stdenv,
  makeWrapper,
  writeText,
  writeTextFile,
  runCommand,
  callPackage,
  CoreServices,
  ImageIO,
  CoreGraphics,
  xcodePlatform ? stdenv.targetPlatform.xcodePlatform or "MacOSX",
  xcodeVer ? stdenv.targetPlatform.xcodeVer or "9.4.1",
  sdkVer ? stdenv.targetPlatform.darwinSdkVersion or "10.12",
  productBuildVer ? null,
}:

let

  toolchainName = "com.apple.dt.toolchain.XcodeDefault";
  sdkName = "${xcodePlatform}${sdkVer}";
  xcrunSdkName = lib.toLower xcodePlatform;

  # TODO: expose MACOSX_DEPLOYMENT_TARGET in nix so we can use it here.
  sdkBuildVersion = "17E189";
  xcodeSelectVersion = "2349";

  xcbuild = callPackage ./default.nix {
    inherit
      CoreServices
      ImageIO
      CoreGraphics
      stdenv
      ;
  };

  toolchains = callPackage ./toolchains.nix { inherit toolchainName stdenv; };

  sdks = callPackage ./sdks.nix {
    inherit
      toolchainName
      sdkName
      xcodePlatform
      sdkVer
      productBuildVer
      ;
  };

  platforms = callPackage ./platforms.nix { inherit sdks xcodePlatform stdenv; };

  xcconfig = writeText "nix.xcconfig" ''
    SDKROOT=${sdkName}
  '';

  xcode-select = writeText "xcode-select" ''
    #!${stdenv.shell}
    while [ $# -gt 0 ]; do
       case "$1" in
             -h | --help) ;; # noop
             -s | --switch) shift;; # noop
             -r | --reset) ;; # noop
             -v | --version) echo xcode-select version ${xcodeSelectVersion} ;;
             -p | -print-path | --print-path) echo @DEVELOPER_DIR@ ;;
             --install) ;; # noop
        esac
        shift
    done
  '';

  xcrun = writeTextFile {
    name = "xcrun";
    executable = true;
    destination = "/bin/xcrun";
    text = ''
      #!${stdenv.shell}
      args=( "$@" )

      # If an SDK was requested, check that it matches.
      for ((i = 0; i < ''${#args[@]}; i++)); do
        case "''${args[i]}" in
          --sdk | -sdk)
            i=$((i + 1))
            if [[ "''${args[i]}" != '${xcrunSdkName}' ]]; then
              echo >&2 "xcodebuild: error: SDK \"''${args[i]}\" cannot be located."
              exit 1
            fi
            ;;
        esac
      done

      while [ $# -gt 0 ]; do
         case "$1" in
               --sdk | -sdk) shift ;;
               --toolchain | -toolchain) shift ;;
               --find | -find | -f)
                 shift
                 command -v $1 || exit 1 ;;
               --log | -log) ;; # noop
               --verbose | -verbose) ;; # noop
               --no-cache | -no-cache) ;; # noop
               --kill-cache | -kill-cache) ;; # noop
               --show-sdk-path | -show-sdk-path)
                 echo ${sdks}/${sdkName}.sdk ;;
               --show-sdk-platform-path | -show-sdk-platform-path)
                 echo ${platforms}/${xcodePlatform}.platform ;;
               --show-sdk-version | -show-sdk-version)
                 echo ${sdkVer} ;;
               --show-sdk-build-version | -show-sdk-build-version)
                 echo ${sdkBuildVersion} ;;
               *) break ;;
          esac
          shift
      done

      if ! [[ -z "$@" ]]; then
         exec "$@"
      fi
    '';
    checkPhase = ''
      ${stdenv.shellDryRun} "$target"
    '';
  };

in

runCommand "xcodebuild-${xcbuild.version}"
  {
    nativeBuildInputs = [ makeWrapper ];
    inherit (xcbuild) meta;

    # ensure that the toolchain goes in PATH
    propagatedBuildInputs = [ "${toolchains}/XcodeDefault.xctoolchain" ];

    passthru = {
      inherit xcbuild xcrun;
      toolchain = "${toolchains}/XcodeDefault.xctoolchain";
      sdk = "${sdks}/${sdkName}";
      platform = "${platforms}/${xcodePlatform}.platform";
    };

    preferLocalBuild = true;
  }
  ''
    mkdir -p $out/bin

    ln -s $out $out/usr

    mkdir -p $out/Library/Xcode
    ln -s ${xcbuild}/Library/Xcode/Specifications $out/Library/Xcode/Specifications

    ln -s ${platforms} $out/Platforms
    ln -s ${toolchains} $out/Toolchains

    mkdir -p $out/Applications/Xcode.app/Contents
    ln -s $out $out/Applications/Xcode.app/Contents/Developer

    # The native xcodebuild command supports an invocation like "xcodebuild -version -sdk" without specifying the specific SDK, so we simulate this by
    # detecting this case and simulating the output; printing the header and appending the normal output via appending the sdk version to the positional
    # arguments we pass through to the wrapped xcodebuild.
    makeWrapper ${xcbuild}/bin/xcodebuild $out/bin/xcodebuild \
      --add-flags "-xcconfig ${xcconfig}" \
      --add-flags "DERIVED_DATA_DIR=." \
      --set DEVELOPER_DIR "$out" \
      --set SDKROOT ${sdkName} \
      --run '[ "$#" -eq 2 ] && [ "$1" = "-version" ] && [ "$2" = "-sdk" ] && echo ${sdkName}.sdk - macOS ${sdkVer} \(macosx${sdkVer}\) && set -- "$@" "${sdkName}"' \
      --run '[ "$1" = "-version" ] && [ "$#" -eq 1 ] && (echo Xcode ${xcodeVer}; echo Build version ${sdkBuildVersion}) && exit 0' \
      --run '[ "$1" = "-license" ] && exit 0'

    substitute ${xcode-select} $out/bin/xcode-select \
      --subst-var-by DEVELOPER_DIR $out/Applications/Xcode.app/Contents/Developer
    chmod +x $out/bin/xcode-select

    cp ${xcrun}/bin/xcrun $out/bin/xcrun

    for bin in PlistBuddy actool builtin-copy builtin-copyPlist \
               builtin-copyStrings builtin-copyTiff \
               builtin-embeddedBinaryValidationUtility \
               builtin-infoPlistUtility builtin-lsRegisterURL \
               builtin-productPackagingUtility builtin-validationUtility \
               lsbom plutil; do
      ln -s ${xcbuild}/bin/$bin $out/bin/$bin
    done

    fixupPhase
  ''