CSS missing, search non-functional and cannot display docs (hoogleLocal from nixos-unstable)

I'm not sure if this is a nixpkgs problem or a hoogle issue. Regardless, if you use the hoogleLocal function in nixpkgs on nixos-unstable (which has Hoogle 5.0.17.11) the resulting hoogle executable runs, but does not function. Here is a minimal shell.nix to reproduce the issue:

let
  nixpkgsBootstrap = import <nixpkgs> {};
  pkgs = import (nixpkgsBootstrap.fetchFromGitHub {
    owner = "NixOS";
    repo = "nixpkgs-channels";
    rev = "7d5375ebf4cd417465327d7ab453687fd19663c9"; # nixos-unstable head
    sha256 = "18myjqws6mm4xsx4nx348yix793wyk76dyklls6dgyp9rg0gfcma"; 
  }) {};
in
  pkgs.mkShell {
    buildInputs = [
        (pkgs.haskellPackages.hoogleLocal {})
      ];
    }

Start by reproducing the issue with the provided shell.nix and the Hoogle 5.0.17.11 hoogleLocal executable. Trace how the executable serves CSS, search results, and documentation, then compare each failing path with the expected behavior. Done means the executable loads its CSS, performs searches, and displays documentation successfully.