# Read actual constructor attributes as comparison data. Their values AND
# dependency contexts remain visible; none is substituted for a build input.
derivation:
let
  fields = [
    "name"
    "system"
    "src"
    "stdenv"
    "nativeBuildInputs"
    "buildInputs"
    "propagatedBuildInputs"
    "propagatedNativeBuildInputs"
    "configurePhase"
    "buildPhase"
    "checkPhase"
    "installPhase"
    "doCheck"
    "strictDeps"
    "outputs"
    "__structuredAttrs"
  ];
  selected = builtins.intersectAttrs (builtins.listToAttrs (
    map (name: {
      inherit name;
      value = null;
    }) fields
  )) derivation;
in
builtins.mapAttrs (_: value: {
  type = builtins.typeOf value;
  value = builtins.unsafeDiscardStringContext (toString value);
  context = builtins.getContext (toString value);
}) selected