{
  description = "Voice-activated eye pressure classifier";

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

  outputs = { self, nixpkgs, flake-utils }:
    flake-utils.lib.eachDefaultSystem (system:
      let
        pkgs = import nixpkgs {
          inherit system;
          config.allowUnfree = true;
          config.cudaSupport = true;
        };
      in
      {
        devShells.default = pkgs.mkShell {
          buildInputs = with pkgs; [
            # Python and uv
            python313
            uv

            # Audio
            portaudio
            pipewire
            alsa-lib
            ffmpeg

            # CUDA (for faster-whisper)
            cudaPackages.cudatoolkit
            cudaPackages.cudnn

            # SSL certificates
            cacert

            # Text-to-speech
            espeak-ng
          ];

          shellHook = ''
            export LD_LIBRARY_PATH="${pkgs.lib.makeLibraryPath [
              pkgs.portaudio
              pkgs.pipewire
              pkgs.alsa-lib
              pkgs.cudaPackages.cudatoolkit
              pkgs.cudaPackages.cudnn
            ]}:/run/opengl-driver/lib:$LD_LIBRARY_PATH"

            export SSL_CERT_FILE="${pkgs.cacert}/etc/ssl/certs/ca-bundle.crt"
            export REQUESTS_CA_BUNDLE="$SSL_CERT_FILE"

            echo "Voice classifier dev environment"
            echo "Run: uv run python listener.py"
          '';
        };
      }
    );
}