{
  config,
  lib,
  pkgs,
  namespace,
  ...
}:
let
  gpuTargets = [ "gfx1102" ]; # todo update when support is added gfx1150
in
{
  programs.ccache = {
    enable = true;
    packageNames = [
      "dolphin-emu"
      # "ffmpeg"
      "ffmpeg_8"
      "ffmpeg_7"
      "ffmpeg_6"
      "ffmpeg-full"
      "gamescope"
      "gjs"
      "gst-plugins-bad"
      "gst-plugins-rs"
      "gtk4"
      "hipblaslt"
      "jemalloc"
      "jupiter-fan-control"
      "libcamera-rpi"
      "libsecret"
      "linux"
      "linux-rpi"
      "linuxPackages_cachyos"
      "linuxPackages_cachyos-lto"
      "linuxPackages_cachyos-lto-znver4"
      "linuxPackages_cachyos-server"
      "linuxPackages_cachyos-server-lto"
      "linuxPackages_cachyos-server-lto-znver4"
      "linuxPackages_cachyos-rc"
      "linuxPackages_cachyos-rc-lto"
      "linuxPackages_cachyos-rc-lto-znver4"
      "linuxPackages_cachyos-hardened"
      "linuxPackages_cachyos-hardened-lto"
      "linuxPackages_cachyos-hardened-lto-znver4"
      "mesa"
      "mesa_i686"
      "mesa-radeonsi-jupiter"
      "mesa-radv-jupiter"
      "mgba"
      "orca-slicer"
      # "onnxruntime"
      "opencv"
      "opencv4"
      "opencv4WithoutCuda"
      "pipewire"
      "qemu"
      "qemu_kvm"
      "qemu_full"
      "qt3d"
      "qtdeclarative"
      "qtmultimedia"
      "ryubing"
      "sdl"
      "sdl2"
      "sdl3"
      "uv"
      "webkitgtk"
    ];
    cacheDir = "/var/cache/ccache"; # default location
  };

  nixpkgs.overlays = [
    (_self: super: {
        ${namespace} = super.${namespace} // {
          linux-rpi = super.${namespace}.linux-rpi.override { stdenv = super.ccacheStdenv; };
          linuxPackages_rpi4 = super.linuxPackagesFor (super.${namespace}.linux-rpi.override { stdenv = super.ccacheStdenv; rpiVersion = 4; });
          linuxPackages_rpi5 = super.linuxPackagesFor (super.${namespace}.linux-rpi.override { stdenv = super.ccacheStdenv; });
          libraspberrypi = super.${namespace}.libraspberrypi.override { stdenv = super.ccacheStdenv; };
          raspberrypi-utils = super.${namespace}.raspberrypi-utils.override { stdenv = super.ccacheStdenv; };
        };
    })
    
    (_self: super: {
      "raspberrypi-utils" = super.${namespace}."raspberrypi-utils";
      "raspberrypi-udev-rules" = super.${namespace}."udev-rules";
    })
    (_self: super: {
      "mesa" = super."mesa".override { buildPackages.stdenv = super.ccacheStdenv; };
    })
    (_self: super: {
      "raspberrypi-utils" = super.${namespace}."raspberrypi-utils";
    })
    (_self: super: {
      electron = super.stable.electron-bin;
      electron_36 = super.stable.electron_36-bin;
      electron_37 = super.stable.electron_37-bin;
    })
    # (_self: super: {
    #   "webkitgtk_4_1" = super.stable."webkitgtk_4_1".override { clangStdenv = super.ccacheStdenv; };
    # })
    # (_self: super: {
    #   "webkitgtk_6_0" = super."webkitgtk_6_0".override { clangStdenv = super.ccacheStdenv; };
    # })
    (_self: super: {
      "jellyfin-ffmpeg" = super."jellyfin-ffmpeg".override {
        ffmpeg_7-full = super.ffmpeg_7-full.override { stdenv = super.ccacheStdenv; };
      };
    })
    # (self: super: {
    #   "ffmpeg-headless-rpi" = super."ffmpeg-headless-rpi".override { ffmpeg = super.ffmpeg_7.override { stdenv = super.ccacheStdenv; }; };
    # })

    # todo: make these work
    (_self: super: {
      rocmPackages = super.stable.rocmPackages;
      piper-tts = super.stable.piper-tts;
      python3Packages = super.python3Packages // {
        torch = super.stable.python3Packages.torch;
      };
    })
    # (_self: super: {
    #   rocmPackages = super.rocmPackages // {
    #     hipblaslt = super.rocmPackages.hipblaslt.override {
    #       stdenv = super.ccacheStdenv;
    #       inherit gpuTargets;
    #     };
    #     rocblas = super.rocmPackages.rocblas.override {
    #       # stdenv = super.ccacheStdenv;
    #       inherit gpuTargets;
    #     };
    #     rocsolver = super.rocmPackages.rocsolver.override {
    #       # stdenv = super.ccacheStdenv;
    #       inherit gpuTargets;
    #     };
    #   };
    # })
    (_self: super: {
      pcsx2 = super.pcsx2.override {
        llvmPackages = super.llvmPackages // {
          stdenv = super.ccacheStdenv;
        };
      };
    })
    (_self: super: {
      driversi686Linux = super.driversi686Linux // {
        mesa = super.driversi686Linux.mesa.override {
          stdenv = super.ccacheStdenv;
          buildPackages = super.driversi686Linux.mesa.buildPackages // {
            stdenv = super.ccacheStdenv;
          };
        };
      };
    })
    (_self: super: {
      kdePackages = super.kdePackages // {
        qt3d = super.kdePackages.qt3d.override {
          qtbase = super.kdePackages.qtbase.override { stdenv = super.ccacheStdenv; };
        };
        qtwebengine = super.stable.kdePackages.qtwebengine; #.override { stdenv = super.ccacheStdenv; };
      };
    })
    # (_self: super: {
    #   python3Packages = super.python3Packages // {
    #     torch = super.python3Packages.torch.override {
    #       stdenv = super.ccacheStdenv;
    #       inherit gpuTargets;
    #     };
    #   };
    # })
    # (_self: super: {
    #   piper-tts = super.piper-tts.overridePythonAttrs (oldAttrs: {
    #     pythonCatchConflictsPhase = null;
    #   });
    # })
  ];

  nix = {
    settings = {
      extra-sandbox-paths = [ config.programs.ccache.cacheDir ];
      substituters = [
        "https://cache.mjallen.dev/nas-cache"
        "https://nixos-raspberrypi.cachix.org"
        "https://nix-community.cachix.org"
        "https://cache.nixos.org/"
      ];
      trusted-public-keys = [
        "nas-cache:Y7PR+XTLr1bLIL85PKb9Tk9/BnE5HndTKvZYWVP1/48="
        "nixos-raspberrypi.cachix.org-1:4iMO9LXa8BqhU+Rpg6LQKiGa2lsNh/j2oiYLNOQ5sPI="
        "nix-community.cachix.org-1:mB9FSh9qf2dCimDSUo8Zy7bkq5CX+/rkCWyvRCYg3Fs="
      ];
      warn-dirty = lib.mkForce false;
      experimental-features = lib.mkForce [
        "nix-command"
        "flakes"
      ];
      trusted-users = [ "@wheel" ];
    };

    # Garbage collect automatically every week
    gc.automatic = lib.mkDefault true;
    gc.options = lib.mkDefault "--delete-older-than 30d";

    optimise.automatic = lib.mkDefault true;
  };

  nixpkgs = {
    config = {
      cudaSupport = lib.mkDefault config.${namespace}.hardware.nvidia.enable;
      rocmSupport = lib.mkDefault config.${namespace}.hardware.amd.enable;
      allowUnsupportedSystem = true;
    };
  };
}