anchor.diff: -{ lib, stdenv
  +{ lib
  +, stdenv
   , fetchFromGitHub
   , dos2unix
   , edid-decode
   , hexdump
   , zsh
  -, modelines ? [] # Modeline "1280x800"   83.50  1280 1352 1480 1680  800 803 809 831 -hsync +vsync
  +, modelines ? [ ] # Modeline "1280x800"   83.50  1280 1352 1480 1680  800 803 809 831 -hsync +vsync
  +, clean ? false # should it skip all, but explicitly listed modelines?
   }:
  +
  +# Usage:
  +#   (edid-generator.override {
  +#     clean = true;
  +#     modelines = [
  +#       ''Modeline "PG278Q_2560x1440"       241.50   2560 2608 2640 2720   1440 1443 1448 1481   -hsync +vsync''
  +#       ''Modeline "PG278Q_2560x1440@120"   497.75   2560 2608 2640 2720   1440 1443 1448 1525   +hsync -vsync''
  +#       ''Modeline "U2711_2560x1440"        241.50   2560 2600 2632 2720   1440 1443 1448 1481   -hsync +vsync''
  +#     ];
  +#   })
   
   stdenv.mkDerivation rec {
     pname = "edid-generator";
  
positive.code:     description = "Hackerswork to generate an EDID blob from given Xorg Modelines";
      homepage = "https://github.com/akatrevorjay/edid-generator";
      license = lib.licenses.mit;
      maintainers = [ lib.maintainers.flokli ];
      platforms = lib.platforms.all;
      broken = stdenv.isDarwin; # never built on Hydra https://hydra.nixos.org/job/nixpkgs/trunk/edid-generator.x86_64-darwin
    };
  
negative.code: 
    postPatch = ''
      patchShebangs modeline2edid
      # allows makefile to discover prefixes and suffixes in addition to just `[0-9]*x[0-9]*.S`
      awk -i inplace '/^SOURCES\t/ { print "SOURCES\t:= $(wildcard *[0-9]*x[0-9]**.S)"; next; }; { print; }' Makefile
    '';
  
    configurePhase = ''
      test '${toString clean}' != 1 || rm *x*.S
      ${lib.concatMapStringsSep "\n" (m: "./modeline2edid - <<<'${m}'") modelines}
      make clean all
    '';
  
    installPhase = ''
      install -Dm 444 *.bin -t "$out/lib/firmware/edid"
  