anchor.diff:  { stdenv, lib, buildPackages, fetchFromGitHub, perl, buildLinux, rpiVersion, ... } @ args:
   
   let
  -  modDirVersion = "4.19.118";
  -  tag = "1.20200601";
  +  modDirVersion = "5.4.51";
  +  tag = "1.20200819";
   in
   lib.overrideDerivation (buildLinux (args // {
     version = "${modDirVersion}-${tag}";
  
positive.code:     "3" = if stdenv.hostPlatform.isAarch64 then "bcmrpi3_defconfig" else "bcm2709_defconfig";
      "4" = "bcm2711_defconfig";
    }.${toString rpiVersion};
  
    features = {
      efiBootStub = false;
  
negative.code:     owner = "raspberrypi";
      repo = "linux";
      rev = "raspberrypi-kernel_${tag}-1";
      sha256 = "0n23q5mm2jyi42m0a45mx0add12pcc5jmfkd858s3v2d5g3bb1f0";
    };
  
    defconfig = {
  