{
  description = "A simple flake";

  inputs.nixpkgs.url = "nixpkgs/nixos-unstable";

  outputs = { self, nixpkgs }: {

    defaultPackage.x86_64-linux = let
      pkgs = nixpkgs.legacyPackages.x86_64-linux;
      python = pkgs.python311;
      pythonPackages = python.pkgs;

      modelUrl = "https://huggingface.co/rhasspy/piper-voices/resolve/v1.0.0/en/en_US/hfc_female/medium/en_US-hfc_female-medium.onnx?download=true";
      modelJsonUrl = "https://huggingface.co/rhasspy/piper-voices/resolve/v1.0.0/en/en_US/hfc_female/medium/en_US-hfc_female-medium.onnx.json?download=true.json";

      model = pkgs.fetchurl {
        name = "hfc_female/medium/en_US-hfc_female-medium.onnx";
        url = modelUrl;
        sha256 = "sha256-kUxHN4j8H6i2Os4c3NtEWI9K5SPTqzffFTZhaDWhQLc="; # replace with the correct sha256
      };

      modelJson = pkgs.fetchurl {
        name = "hfc_female/medium/en_US-hfc_female-medium.onnx.json";
        url = modelJsonUrl;
        sha256 = "sha256-A/H6BiK4BGMoNZLZesqfbomuw0WlxWtyV3I+AJPFi2w="; # replace with the correct sha256
      };
    in pkgs.mkShell {
      nativeBuildInputs = with pkgs; [
        python
        piper-tts
        alsa-utils # for aplay for piper-tts to stream to
        
        (pythonPackages.pypdf)

      ];

      shellHook = ''
        mkdir -p piper-models
        cp ${model} piper-models/
        cp ${modelJson} piper-models/
      '';
    };
  };
}