anchor.diff:      owner = "raspberrypi";
       repo = "linux";
       rev = "raspberrypi-kernel_${tag}-1";
  -    sha256 = "11jzsmnd1qry2ir9vmsv0nfdzjpgkn5yab5ylxcz406plc073anp";
  +    sha256 = "0n23q5mm2jyi42m0a45mx0add12pcc5jmfkd858s3v2d5g3bb1f0";
     };
   
     defconfig = {
  
positive.code:     "3" = if stdenv.hostPlatform.isAarch64 then "bcmrpi3_defconfig" else "bcm2709_defconfig";
      "4" = "bcm2711_defconfig";
    }.${toString rpiVersion};
  
    features = {
      efiBootStub = false;
  
negative.code: { stdenv, lib, buildPackages, fetchFromGitHub, perl, buildLinux, rpiVersion, ... } @ args:
  
  let
    modDirVersion = "5.4.51";
    tag = "1.20200819";
  in
  lib.overrideDerivation (buildLinux (args // {
    version = "${modDirVersion}-${tag}";
  