{
  description = "MPV overlay with scripts and configuration for watching anime";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, nixpkgs, utils }: let
    packages = utils.lib.eachDefaultSystem (system: let
      pkgs = import nixpkgs { inherit system; };
      mpvScript = { owner, repo, rev, sha256, scriptName }: pkgs.stdenvNoCC.mkDerivation {
        pname = repo;
        version = builtins.substring 0 6 rev;
        src = pkgs.fetchFromGitHub {
          inherit owner repo rev sha256;
        };
        dontBuild = true;
        installPhase = ''
          install -Dm644 ${scriptName} $out/share/mpv/scripts/${scriptName}
        '';
        passthru = { inherit scriptName; };
      };
    in {
      packages.sub-select = mpvScript {
        owner = "CogentRedTester";
        repo = "mpv-sub-select";
        rev = "5d2fb7ab73fc0e36d44109e75c9be26bd42084e2";
        sha256 = "0dyh2kyvivj81lrkyqhc3czmi9hqjkh7xg8dqjnnr3kh3yn62dpi";
        scriptName = "sub-select.lua";
      };

      packages.segment-linking = mpvScript {
        owner = "CogentRedTester";
        repo = "mpv-segment-linking";
        rev = "bb0fdb7961859df57c64b42d75dbbd60a4024e97";
        sha256 = "1ykl24p96wwka4fillrzni6i0xkk4s2l9zg1scqypcbs5w491qsj";
        scriptName = "segment-linking.lua";
      };
    });
  in
    packages // rec {
      overlays.default = final: prev: let
        newScripts = packages.packages.${prev.system};
      in {
        mpv = prev.mpv.override { scripts = builtins.attrValues newScripts; };
        mpvScripts = prev.mpvScripts // newScripts;
      };

      nixosModules.default = { pkgs, lib, ... }: {
        nixpkgs.overlays = [ overlays.default ];

        # needed for mpv segment-linking plugin
        environment.systemPackages = [
          pkgs.mkvtoolnix
        ];

        home-manager.sharedModules = [ ({ config, ... }: {
          config = lib.mkIf config.programs.mpv.enable {
            xdg.configFile."mpv/script-opts/sub-select.json".text = builtins.toJSON [
              # English audio:
              # 1. English signs/songs subs
              # 2. Forced subs
              # 3. No subs
              {
                alang = "eng?";
                slang = "eng?";
                whitelist = [ "sign" "song" ];
              }
              {
                alang = "eng?";
                slang = "forced";
              }
              {
                alang = [ "eng?" "no" ];
                slang = "no";
              }

              # Non-English audio:
              # 1. English non-signs non-forced subs, default subs iff default audio
              # 2. English non-signs non-forced subs
              # 3. English non-signs forced subs
              # 4. Undefined non-signs non-forced subs, default subs iff default audio
              # 5. Undefined non-signs non-forced subs
              # 6. Undefined non-signs forced subs
              # 7. English signs/songs subs, I guess
              # 8. Undefined signs/songs subs, I guess
              # 9. Forced subs in other languages, I guess
              {
                alang = "*";
                slang = "eng?";
                blacklist = [ "sign" "song" ];
                condition = "not sub.forced and ((audio.default and sub.default) or (not audio.default and not sub.default))";
              }
              {
                alang = "*";
                slang = "eng?";
                blacklist = [ "sign" "song" ];
                condition = "not sub.forced";
              }
              {
                alang = "*";
                slang = "eng?";
                blacklist = [ "sign" "song" ];
              }
              {
                alang = "*";
                slang = "und";
                blacklist = [ "sign" "song" ];
                condition = "not sub.forced and ((audio.default and sub.default) or (not audio.default and not sub.default))";
              }
              {
                alang = "*";
                slang = "und";
                blacklist = [ "sign" "song" ];
                condition = "not sub.forced";
              }
              {
                alang = "*";
                slang = "und";
                blacklist = [ "sign" "song" ];
              }
              {
                alang = "*";
                slang = "eng?";
              }
              {
                alang = "*";
                slang = "und";
              }
              {
                alang = "*";
                slang = "forced";
              }
            ];
          };
        }) ];
      };
    };
}