anchor.diff:      }
   
       query() {
  -      nix-env -qaP --description | grep -i $@
  +      ${nix}/bin/nix-env -f "${NIX_MY_PKGS}" -qaP --description | grep -i $@
  +    }
  +
  +    installed() {
  +      ${nix}/bin/nix-env -f "${NIX_MY_PKGS}" -q $@
       }
   
       install() {
  -      nix-env -iA $@
  +      ${nix}/bin/nix-env -f "${NIX_MY_PKGS}" -iA $@
  +    }
  +
  +    erase() {
  +      if [ -z "$1" ]; then
  +        echo "argument is required"
  +        exit 1
  +      else
  +        ${nix}/bin/nix-env -f "${NIX_MY_PKGS}" -e $@
  +      fi
       }
   
       build() {
  -      nix-build '<nixpkgs>' -A $1
  +      ${nix}/bin/nix-build '<nixpkgs>' -A $1
       }
   
       just-build() {
  -      nix-build '<nixpkgs>' --no-out-link -A $1
  +      ${nix}/bin/nix-build '<nixpkgs>' --no-out-link -A $1
       }
   
       command() {
  
positive.code:         echo "$1 not found"
          exit 1
        fi
      }
  
      help() {
  
negative.code:   NIX_PATH = "nixpkgs=${NIX_MY_PKGS}:nixos=${NIX_MY_PKGS}/nixos:nixos-config=${NIXOS_CONFIG}:services=${NIXOS_SERVICES}";
  
    # this is a command and not a function, to work with nox
    nixenv = pkgs.writeScriptBin "nixenv" ''
      #!${pkgs.stdenv.shell}
      ${nix}/bin/nix-env -f "${NIX_MY_PKGS}" "$@"
    '';
  
    nixmyEnv = pkgs.buildEnv {
      name = "nixmyEnv";
      paths = [ pkgs.wget pkgs.git nixenv nix ] ++ extraPaths;
    };
  
    nixmy = pkgs.writeScriptBin "nixmy" ''
  