{
  inputs.nixpkgs.url = "github:NixOS/nixpkgs/nixos-unstable";

  outputs =
    {
      self,
      nixpkgs,
      ...
    }:
    let
      inherit (nixpkgs) lib;
      forAllSystems = lib.genAttrs lib.systems.flakeExposed;
    in
    {
      packages = forAllSystems (
        system:
        let
          pkgs = nixpkgs.legacyPackages.${system};
        in
        {
          default = pkgs.buildGoModule {
            pname = "hello_go";
            version = "0.0.1";
            src = self;

            # The "Trust but Verify" hash.
            vendorHash = null;
          };
        }
      );

      devShells = forAllSystems (
        system:
        let
          pkgs = nixpkgs.legacyPackages.${system};
        in
        {
          default = pkgs.mkShellNoCC {
            packages = with pkgs; [
              go
              gopls
              gotools
              go-tools
            ];
          };
        }
      );
    };
}