{
  description = "A very basic flake";
  outputs = { self, nixpkgs }: {
    packages.x86_64-linux.hello = nixpkgs.legacyPackages.x86_64-linux.hello;
    defaultPackage.x86_64-linux = self.packages.x86_64-linux.hello;
  };
}

{
  "nodes": {
    "nixpkgs": {
      "locked": {
        "lastModified": 1626215871,
        "narHash": "sha256-OefVqwnB6vfDXX3j55kb22/Q5tXQkTB1p3hBWxB3ZuY=",
        "owner": "NixOS",
        "repo": "nixpkgs",
        "rev": "a68f9c2b77662562249f7a11a9cc736d0b28f6af",
        "type": "github"
      },
      "original": {
        "id": "nixpkgs",
        "type": "indirect"
      }
    },
    "root": {
      "inputs": {
        "nixpkgs": "nixpkgs"
      }
    }
  },
  "root": "root",
  "version": 7
}

result