{
  description = "Scobleclaw — NixOS + home-manager configuration for personal laptop (x86_64) and work Mac (aarch64)";

  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";
    home-manager = {
      url = "github:nix-community/home-manager";
      inputs.nixpkgs.follows = "nixpkgs";
    };
    pi-mono = {
      url = "git+https://os.scoble.me/forgejo/sscoble/pi-mono.git";
      flake = false;
    };
    nixos-hardware.url = "github:NixOS/nixos-hardware/master";
  };

  outputs = { self, nixpkgs, home-manager, pi-mono, nixos-hardware, ... }@inputs: let
    linuxSystem = "x86_64-linux";
    darwinSystem = "aarch64-darwin";

    # Linux pkgs with overlay (pi, qmd)
    linuxPkgs = import nixpkgs {
      system = linuxSystem;
      overlays = [ self.overlays.default ];
    };
  in {
    # === Overlay: pi + qmd (Linux only) ===
    overlays.default = final: prev: {
      pi-coding-agent = final.buildNpmPackage {
        pname = "pi-coding-agent";
        version = "0.73.0";
        src = pi-mono;
        npmDepsHash = "";  # Fill after first build
        npmWorkspace = "packages/coding-agent";
        npmFlags = [ "--legacy-peer-deps" ];
        dontNpmBuild = true;
        preConfigure = ''
          cd packages/ai && npm run build && cd ../..
          cd packages/agent && npm run build && cd ../..
          cd packages/tui && npm run build && cd ../..
          cd packages/coding-agent && npm run build && cd ../..
        '';
        installPhase = ''
          runHook preInstall
          mkdir -p $out/lib/node_modules/@mariozechner/pi-coding-agent
          cp -r packages/coding-agent/dist $out/lib/node_modules/@mariozechner/pi-coding-agent/
          cp packages/coding-agent/package.json $out/lib/node_modules/@mariozechner/pi-coding-agent/
          mkdir -p $out/bin
          cat > $out/bin/pi <<'EOF'
          #!/usr/bin/env bash
          exec ${final.nodejs}/bin/node $out/lib/node_modules/@mariozechner/pi-coding-agent/dist/cli.js "$@"
          EOF
          chmod +x $out/bin/pi
          runHook postInstall
        '';
      };

      qmd = final.writeShellScriptBin "qmd" ''
        exec ${final.bun}/bin/bunx --bun @tobilu/qmd "$@"
      '';
    };

    # === NixOS: full system + desktop ===
    nixosConfigurations.laptop = nixpkgs.lib.nixosSystem {
      system = linuxSystem;
      modules = [
        home-manager.nixosModules.home-manager
        ./modules/laptop.nix
        ./modules/hyprland.nix
        ./modules/t490.nix
        nixos-hardware.nixosModules.lenovo-thinkpad-t490
        { nixpkgs.config.allowUnfree = true; }
        {
          home-manager = {
            useGlobalPkgs = true;
            useUserPackages = true;
            users.sscoble = {
              imports = [
                ./home/sscoble.nix
                ./home/desktop.nix
                ./home/wgu.nix
              ];
            };
          };
        }
      ];
    };

    # === VM: minimal NixOS for testing (aarch64, UTM) ===
    nixosConfigurations.vm = nixpkgs.lib.nixosSystem {
      system = "aarch64-linux";
      modules = [
        home-manager.nixosModules.home-manager
        ./modules/vm.nix
        { nixpkgs.config.allowUnfree = true; }
        {
          home-manager = {
            useGlobalPkgs = true;
            useUserPackages = true;
            users.sscoble = {
              imports = [
                ./home/sscoble.nix
                ./home/wgu.nix
              ];
            };
          };
        }
      ];
    };

    # === macOS: home-manager standalone (no desktop, no Hyprland) ===
    homeConfigurations.sscoble = home-manager.lib.homeManagerConfiguration {
      pkgs = nixpkgs.legacyPackages.${darwinSystem};
      modules = [
        ./home/sscoble.nix
        ./home/wgu.nix
        {
          home.homeDirectory = "/Users/sscoble";
          nixpkgs.config.allowUnfree = true;
        }
      ];
    };

    # === Dev shell (Linux) ===
    devShells.${linuxSystem}.default = linuxPkgs.mkShell {
      buildInputs = with linuxPkgs; [
        pi-coding-agent
        qmd
        nodejs
        bun
        git
        zsh
      ];
      shellHook = ''
        echo "🦞 Scobleclaw dev shell"
        echo "  pi:      $(which pi)"
        echo "  qmd:     $(which qmd)"
        echo "  node:    $(node --version)"
        echo "  bun:     $(bun --version)"
      '';
    };
  };
}