let nixpkgs' = (import <nixpkgs> {});
    pkgs = nixpkgs' // { lib = nixpkgs'.lib.extend (self: super: { inNixShell = false; }); };
in pkgs.haskell.lib.overrideCabal (import ./shell-gen.nix { nixpkgs = pkgs; compiler = "ghcjs84"; })
  (drv: { buildDepends = (drv.buildDepends or []) ++ [ pkgs.haskell.packages.ghc843.cabal-install ]; })