anchor.diff:      };
   
     realtimeConfig = { version, enableLatencytop, enableOptimization }:
  -    with (lib.kernel);
  -    with (lib.kernel.whenHelpers version);
  +    with (whenHelpers version);
       (standardConfig { inherit version enableLatencytop enableOptimization; }) // {
         PREEMPT = whenOlder "5.4" yes; # PREEMPT_RT deselects it.
         PREEMPT_RT_FULL = whenOlder "5.4" yes; # Renamed to PREEMPT_RT when merged into the mainline.
  
positive.code:     enableLatencytop ? cfg.kernel.latencytop,
      enableOptimization ? cfg.kernel.optimize
    }:
      with (lib.kernel);
      with (lib.kernel.whenHelpers version);
      lib.optionalAttrs enableLatencytop {
        LATENCYTOP = yes;
        SCHEDSTATS = yes;
  
negative.code: 
  let
  
    inherit (super) lib callPackage linuxPackagesFor recurseIntoAttrs;
  
    # Since 20.09 this is a part of lib.kernel
    option = x:
        x // { optional = true; };
  
    yes      = { tristate    = "y"; optional = false; };
    no       = { tristate    = "n"; optional = false; };
    module   = { tristate    = "m"; optional = false; };
    freeform = x: { freeform = x; optional = false; };
  
    whenHelpers = version: with lib; {
      whenAtLeast = ver: mkIf (versionAtLeast version ver);
      whenOlder   = ver: mkIf (versionOlder version ver);
      # range is (inclusive, exclusive)
      whenBetween = verLow: verHigh: mkIf (versionAtLeast version verLow && versionOlder version verHigh);
    };
  
    cfg = super.config.musnix or {
      kernel.latencytop = false;
  