{
  description = "Python Text RPG Dungeon Crawler";

  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;};
      python = pkgs.python312;

      pythonEnv = python.withPackages (ps:
        with ps; [
          # Dev / QoL
          ipython

          # Testing
          pytest
          pytest-cov

          # Linting & formatting
          ruff
          mypy
        ]);
    in {
      devShells.default = pkgs.mkShell {
        packages = [
          pythonEnv
          pkgs.just # optional: task runner (like make)
        ];

        shellHook = ''
          echo "🐍 Python $(python --version) — TextRPG env ready"
        '';
      };
    });
}