let
  nixpkgs = import (builtins.fetchTarball (builtins.fromJSON (builtins.readFile ./nixpkgs.json))) { };
  stable2105 = import (builtins.fetchTarball (builtins.fromJSON (builtins.readFile ./nixpkgs-2105.json))) { };
in
{ pkgs ? nixpkgs }:
pkgs.mkShell {
  NIX_PATH = "nixpkgs=${nixpkgs.path}";
  buildInputs = [
    pkgs.morph
    stable2105.vagrant
    pkgs.jp
  ];
}