anchor.diff:        "CC_${stdenv.hostPlatform.config}"="${ccForHost}" \
         "CXX_${stdenv.hostPlatform.config}"="${cxxForHost}" \
         cargo build \
  -        --release \
  +        --${buildType} \
           --target ${stdenv.hostPlatform.config} \
           --frozen ${concatStringsSep " " cargoBuildFlags}
       )
  
positive.code: , cargoUpdateHook ? ""
  , cargoDepsHook ? ""
  , cargoBuildFlags ? []
  
  , cargoVendorDir ? null
  , ... } @ args:
  
  assert cargoVendorDir == null -> cargoSha256 != "unset";
  
  let
    cargoDeps = if cargoVendorDir == null
  
negative.code:   cxxForBuild="${buildPackages.stdenv.cc}/bin/${buildPackages.stdenv.cc.targetPrefix}c++";
    ccForHost="${stdenv.cc}/bin/${stdenv.cc.targetPrefix}cc";
    cxxForHost="${stdenv.cc}/bin/${stdenv.cc.targetPrefix}c++";
    releaseDir = "target/${stdenv.hostPlatform.config}/${buildType}";
  
  in stdenv.mkDerivation (args // {
    inherit cargoDeps;
  