{
  description = "Dev shell with .NET 9";

  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;
        };
      in {
        devShells.default = pkgs.mkShell {
          packages = [
            pkgs.dotnet-sdk_9
            # alternativ/zusätzlich:
            # pkgs.dotnetCorePackages.sdk_9_0
          ];
        };
      });
}