{
  description = "Wallpaper renamer: auto-rename images to descriptive snake_case names using a local vision model (Ollama + llava).";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-25.05";
    flake-utils.url = "github:numtide/flake-utils";
  };

  outputs = { self, nixpkgs, flake-utils }:
    flake-utils.lib.eachDefaultSystem (system:
      let
        pkgs = import nixpkgs { inherit system; };

        # The rename command. It starts an Ollama server (if needed) and pulls the
        # vision model on first run, so everything lives inside this shell.
        rename-wallpapers = pkgs.writeScriptBin "rename-wallpapers"
          (builtins.readFile ./rename-wallpapers.py);
      in
      {
        packages.default = rename-wallpapers;

        devShells.default = pkgs.mkShell {
          name = "wallpaper-renamer";
          packages = [
            pkgs.ollama
            pkgs.python3
            pkgs.curl
            pkgs.ffmpeg
            pkgs.fzf
            pkgs.chafa
            rename-wallpapers
          ];

          shellHook = ''
            echo "wallpaper-renamer shell ready."
            echo "Usage examples:"
            echo "  rename-wallpapers                 # rename all images in this dir"
            echo "  rename-wallpapers --pick          # interactively choose with fzf"
            echo "  rename-wallpapers --dir ~/Pics    # scan another directory"
            echo "  rename-wallpapers --dry-run *.jpg # preview without renaming"
            echo "Model is pulled on first run (one-time download)."
          '';
        };
      });
}