{
  inputs = {
    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
    systems.url = "github:nix-systems/default";
  };

  outputs =
    { nixpkgs, ... }:
    let
      eachSystem =
        f:
        nixpkgs.lib.genAttrs nixpkgs.lib.systems.flakeExposed (system: f nixpkgs.legacyPackages.${system});
    in
    {
      devShells = eachSystem (pkgs: {
        default = pkgs.mkShell {
          buildInputs = [
            (pkgs.python3.withPackages (ppkgs: [
              ppkgs.numpy
              ppkgs.torch
            ]))
          ];
        };
      });
    };
}