{
  description = "My personal nix packages";

  inputs.nixpkgs.url = "https://mirrors.cernet.edu.cn/nix-channels/nixos-unstable/nixexprs.tar.xz";

  outputs = { self, nixpkgs }: let
    system = "x86_64-linux";
    myPkgs = import ./overlays/my-pkgs.nix;
    pkgs = import nixpkgs {
      inherit system;
      overlays = [ myPkgs ];
    };
  in {
    overlays = { inherit myPkgs; };
    packages.${system} = pkgs // { default = pkgs.hello-zmsun; };
  };
}