{ description = "niss's silly extra packages";

  outputs = all@{ self, nixpkgs }:
  let
    inherit (nixpkgs.lib) genAttrs optionalAttrs systems defaultTo;
    forAllSystems = genAttrs systems.flakeExposed;


    packagesInDir = dir: names: pkgs:
      let inherit (pkgs) callPackage; in
      genAttrs names (pkg: callPackage ./${dir}/${pkg}.nix {});

    linuxPackages = packagesInDir "apps" [
      "multi-ghc" "basilisk" "isabelle"
      "firefox-esr-alias" "inkscape-xwayland"
    ];

    crossPlatformPackages = packagesInDir "scripts" [ "niss-misc" ];

    fonts = packagesInDir "fonts" [
      "constructium" "fairfax-hd" "kreative-square" "muller"
      "pragmatapro" "teranoptia"
    ];


    makeApp = name: exe:
      { type = "app"; program = "${pkgs.${name}}/bin/${defaultTo name exe}"; };

    linuxApps = pkgs: [
      (makeApp "basilisk" null)
      (makeApp "isabelle" null)
      (makeApp "firefox-esr-alias" "firefox-esr")
      (makeApp "inkscape-xwayland" "inkscape")
    ];


    ifLinux64 = f: pkgs: optionalAttrs (pkgs.system == "x86_64-linux") (f pkgs);

    mkPackages = pkgs:
      ifLinux64 linuxPackages pkgs // crossPlatformPackages pkgs // fonts pkgs;

    mkApps = pkgs: ifLinux64 linuxApps pkgs;
  in {
    packages = forAllSystems (sys: mkPackages nixpkgs.legacyPackages.${sys});
    apps     = forAllSystems (sys: mkApps nixpkgs.legacyPackages.${sys});
    overlays = forAllSystems (sys: final: prev: mkApps final);
  };
}