{
  description = "mat's extra nix pkgs";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";

    helix.url = "github:helix-editor/helix";
    helix.inputs.nixpkgs.follows = "nixpkgs";
    dark-mode-notify-src.url = "github:bouk/dark-mode-notify";
    dark-mode-notify-src.flake = false;
    ia-writer-family-src.url = "github:iaolo/iA-Fonts";
    ia-writer-family-src.flake = false;
    kitty-icon.url = "github:DinkDonk/kitty-icon";
    kitty-icon.flake = false;
    kitty-themes.url = "github:kovidgoyal/kitty-themes";
    kitty-themes.flake = false;
    fisher-src.url = "github:jorgebucaran/fisher";
    fisher-src.flake = false;
  };

  outputs =
    { fisher-src, helix, kitty-icon, kitty-themes, ... }@inputs: {
      overlays =
        let
          overlay = _: prev:
            let
              mkPkg = name: extras: prev.callPackage (./. + name + ".nix")
                {
                  "${name}-src" = inputs."${name}-src";
                } // extras;
            in
            {
              inherit kitty-icon kitty-themes;
              helix = helix.packages.${prev.system}.default;
              fishPlugins.fisher = {
                name = "fisher";
                src = fisher-src;
              };
            } // prev.mapAttrs mkPkg {
              dark-mode-notify = {
                sdkVersion = "14.1";
              };
              ia-writer-family = { };
              yubiswitch = { };
            };
        in
        {
          default = overlay;
          extra-pkgs = overlay;
        };
    };
}