{
  description = "GKleen's flakey openwrt setup";

  inputs = {
    openwrt = {
      type = "github";
      owner = "openwrt";
      repo = "openwrt";
      ref = "master";
      flake = false;
    };
    flake-utils = {
      type = "github";
      owner = "numtide";
      repo = "flake-utils";
      ref = "master";
    };
    nixpkgs = {
      type = "github";
      owner = "NixOS";
      repo = "nixpkgs";
      ref = "master";
    };

    openwrt-packages = {
      url = "git+https://git.openwrt.org/feed/packages.git";
      flake = false;
    };
    openwrt-luci = {
      url = "git+https://git.openwrt.org/project/luci.git";
      flake = false;
    };
    openwrt-routing = {
      url = "git+https://git.openwrt.org/feed/routing.git";
      flake = false;
    };
    openwrt-telephony = {
      url = "git+https://git.openwrt.org/feed/telephony.git";
      flake = false;
    };

    sunwait = {
      type = "github";
      owner = "risacher";
      repo = "sunwait";
      ref = "master";
      flake = false;
    };
  };

  outputs = { self, openwrt, nixpkgs, flake-utils, ... }@inputs: flake-utils.lib.eachDefaultSystem (system:
    let
      pkgs = nixpkgs.legacyPackages.${system};
      
      fixWrapper = pkgs.runCommand "fix-wrapper" {} ''
        mkdir -p $out/bin
        for i in ${pkgs.gcc.cc}/bin/*-gnu-gcc*; do
          ln -s ${pkgs.gcc}/bin/gcc $out/bin/$(basename "$i")
        done
        for i in ${pkgs.gcc.cc}/bin/*-gnu-{g++,c++}*; do
          ln -s ${pkgs.gcc}/bin/g++ $out/bin/$(basename "$i")
        done
      '';

      fhs = extraAttrs: pkgs.buildFHSUserEnvBubblewrap ({
        name = "openwrt-env";
        multiPkgs = null;
        inherit targetPkgs;
        extraOutputsToInstall = [ "dev" ];
        profile = ''
          export NIX_HARDENING_ENABLE=
        '';
      } // extraAttrs);
      targetPkgs = pkgs: with pkgs; [
        binutils
        file
        fixWrapper
        gcc
        getopt
        gettext
        git
        gnumake
        openssl
        patch
        perl
        python2
        python3
        rsync
        subversion
        systemd
        unzip
        wget
        which

        ncurses
        zlib
        # zlib.static
        # glibc.static

        pkgconfig
        ubnt-mkfwimage
        gnused
      ];

      openwrtWithPackages = pkgs.stdenv.mkDerivation {
        name = "openwrt-with-packages";
        src = openwrt;

        phases = [ "unpackPhase" "patchPhase" "buildPhase" "installPhase" ];
        patchPhase = let
          sunwaitRepo = pkgs.runCommand "openwrt-sunwait" {} ''
            mkdir -p $out/utils/sunwait
            cp ${pkgs.writeText "Makefile" ''
              include $(TOPDIR)/rules.mk

              PKG_NAME:=sunwait
              PKG_VERSION:=${inputs.sunwait.rev}
              PKG_RELEASE:=1

              include $(INCLUDE_DIR)/package.mk

              define Package/sunwait
              	SECTION:=util
              	CATEGORY:=Utilities
              	TITLE:=Sunwait
              	URL:=https://github.com/risacher/sunwait
              	DEPENDS:=+libstdcpp +libc
              endef

              define Package/sunwait/description
              	Wait until the specified solar event
              endef

              define Build/Prepare
              	cp --no-preserve=mode --remove-destination -t $(PKG_BUILD_DIR) -r ${inputs.sunwait}/.
              endef

              define Build/Compile
              	$(TARGET_CC) $(TARGET_CPPFLAGS) -o $(PKG_BUILD_DIR)/sunwait.o -c $(PKG_BUILD_DIR)/sunwait.cpp
              	$(TARGET_CC) $(TARGET_CPPFLAGS) -o $(PKG_BUILD_DIR)/sunriset.o -c $(PKG_BUILD_DIR)/sunriset.cpp
              	$(TARGET_CC) $(TARGET_CPPFLAGS) -o $(PKG_BUILD_DIR)/print.o -c $(PKG_BUILD_DIR)/print.cpp
              	$(TARGET_CC) $(TARGET_LDFLAGS) -o $(PKG_BUILD_DIR)/$1 $(PKG_BUILD_DIR)/sunwait.o $(PKG_BUILD_DIR)/sunriset.o $(PKG_BUILD_DIR)/print.o -lm -lstdc++
              endef

              define Package/sunwait/install
              	$(INSTALL_DIR) $(1)/usr/bin
              	$(INSTALL_BIN) $(PKG_BUILD_DIR)/sunwait $(1)/usr/bin/
              endef

              $(eval $(call BuildPackage,sunwait))
            ''} $out/utils/sunwait/Makefile
          '';
          feedsConf = pkgs.writeText "feeds.conf" ''
            src-cpy packages ${inputs.openwrt-packages}
            src-cpy luci ${inputs.openwrt-luci}
            src-cpy routing ${inputs.openwrt-routing}
            src-cpy telephony ${inputs.openwrt-telephony}
            src-cpy sunwait ${sunwaitRepo}
          '';
        in ''
          rm feeds.conf.default
          cp ${feedsConf} feeds.conf
        '';
        buildPhase = ''
          ${let
            runScript = pkgs.writeShellScript "build" ''
              ./scripts/feeds update -a
              ./scripts/feeds install -a
            '';
          in fhs { inherit runScript; }}/bin/openwrt-env
        '';
        installPhase = ''
          cp -r . $out
        '';
      };

      ubnt-mkfwimage = pkgs.stdenv.mkDerivation rec {
        pname = "ubnt-mkfwimage";
        version = "70594ca";
        src = pkgs.fetchFromGitHub {
          owner = "aliosa27";
          repo = "ubnt-mkfwimage";
          rev = version;
          hash = "sha256-NTOSQzRYO/3N2sNLBUa6uzA8LZSshL8W36kW2ociqrA=";
        };

        buildInputs = with pkgs; [ gcc zlib ];

        phases = [ "unpackPhase" "buildPhase" "installPhase" ];
        sourceRoot = "source/src";
        buildPhase = ''
          gcc -lz -o ubnt-mkfwimage ubnt-mkfwimage.c
          gcc -lz -o ubnt-fwsplit fwsplit.c
        '';
        installPhase = ''
          mkdir -p $out/bin
          install -m 0555 -t $out/bin ubnt-mkfwimage ubnt-fwsplit
        '';
      };

      unpackWrt = pkgs.writeShellScript "unpack" ''
        ${pkgs.rsync}/bin/rsync --chmod=u+wX -rlptD --exclude /tmp --exclude /build_dir --exclude /bin --exclude /staging_dir ${openwrtWithPackages}/. ${./files}/. ./.

        patchDir=$(mktemp -d -t patches.XXXXXXXXXX)
        ${pkgs.rsync}/bin/rsync --chmod=u+wX -rlptD ${./patches}/. "''${patchDir}/."

        while IFS= read -r -d $'\0' sopsFile; do
          ${pkgs.sops}/bin/sops --output="''${sopsFile%.sops}" --decrypt "''${sopsFile}"
          rm "''${sopsFile}"
        done < <(find . "$patchDir" -not \( \( -path ./tmp -o -path ./build_dir -o -path ./bin -o -path ./staging_dir \) -a -prune \) -a \( -type f -a -name '*.sops' -a -print0 \))

        while IFS= read -r -d $'\0' patchFile; do
          if [[ "''${patchFile##*.}" = "patch" ]]; then
            patch -p1 --batch <$patchFile
          else
            . $patchFile
          fi
        done < <(find "$patchDir" -type f -print0)
      '';
      buildWrt = pkgs.writeShellScript "build" "make -j1 V=sc";

      buildWrtApp = {
        type = "app";
        program = toString (pkgs.writers.writePython3 "build" {} ''
          from tempfile import TemporaryDirectory
          import os
          import subprocess
          import argparse
          from pathlib import Path

          parser = argparse.ArgumentParser(prog="build",
                                           formatter_class=argparse.ArgumentDefaultsHelpFormatter  # noqa: E501
                                           )
          parser.add_argument('-C', '--directory',
                              dest='dir',
                              metavar='DIRECTORY',
                              type=Path,
                              default=Path('./result'),
                              help='Change to this directory before doing anything'
                              )
          parser.add_argument('--copy-to',
                              dest='copyTo',
                              metavar='FILE',
                              type=Path,
                              default='/srv/tftp/' + Path.cwd().name + '.bin',
                              help='Copy result image here'
                              )
          parser.add_argument('--copy-to-no-sudo',
                              dest='copyToSudo',
                              action='store_false',
                              help='Use sudo to copy result image'
                              )
          parser.add_argument('--copy-image',
                              dest='image',
                              default='bin/targets/ath79/generic/openwrt-ath79-generic-ubnt_unifiac-pro-initramfs-kernel.bin',  # noqa: E501
                              help='Which file to copy'
                              )
          args = parser.parse_args()

          if not args.dir:
              args.dir = Path()
          if not args.copyTo:
              args.copyTo = None

          args.dir.mkdir(parents=True, exist_ok=True)
          os.chdir(args.dir)

          with TemporaryDirectory() as tmpdir:
              os.environ["TMPDIR"] = f"{tmpdir}"
              subprocess.check_call('${fhs { runScript = pkgs.writeShellScript "build" ''
                set +x
                set -e
                ${unpackWrt}
                ${buildWrt}
              ''; }}/bin/openwrt-env')  # noqa: E501

          if args.copyTo:
              command = ['cp', '-v', args.image, args.copyTo]
              if args.copyToSudo:
                  command = ['sudo', '--', *command]
              subprocess.check_call(command)
        '');
      };
    in rec {
      devShell = pkgs.mkShell {
        name = "openwrt";
        shellHook = let
          setup = pkgs.writeText "setup" ''
            set -ex

            function unpackPhase() {
              ${unpackWrt}
            }

            function buildPhase() {
              ${buildWrt}
            }

            set +ex
          '';
        in "exec -- ${fhs { runScript = "bash --init-file ${setup}"; }}/bin/openwrt-env";
      };

      packages = {
        inherit openwrtWithPackages ubnt-mkfwimage;
      };

      apps = {
        inherit buildWrtApp;
      };
      defaultApp = apps.buildWrtApp;
    });
}