anchor.diff:    chell = overrideCabal (doJailbreak super.chell) (_drv: {
       broken = false;
     });
  -  th-expand-syns = doJailbreak super.th-expand-syns;
  -  shelly = overrideCabal (appendPatch (doJailbreak super.shelly) (pkgs.fetchpatch {
  -    url = "https://raw.githubusercontent.com/hvr/head.hackage/master/patches/shelly-1.8.1.patch";
  -    sha256 = "1kglbwrr4ra81v9x3bfsk5l6pyl0my2a1zkr3qjjx7acn0dfpgbc";
  -  })) (drv: {
  -    editedCabalFile = null;
  -    preConfigure = ''
  -      cp -v ${pkgs.fetchurl {url = "https://raw.githubusercontent.com/hvr/head.hackage/master/patches/shelly-1.8.1.cabal"; sha256 = "0crf0m077wky76f5nav2p9q4fa5q4yhv5l4bq9hd073dzdaywhz0";}} shelly.cabal
  -      sed -i -e 's/< 1.9,/< 2,/' shelly.cabal # bump time version
  -    '';
  -  });
  -  system-fileio = doJailbreak super.system-fileio;
  -  tasty-hedgehog = doJailbreak super.tasty-hedgehog;
     haskell-src-meta = appendPatch (dontCheck (doJailbreak super.haskell-src-meta)) (pkgs.fetchpatch {
       url = "https://gitlab.haskell.org/ghc/head.hackage/raw/master/patches/haskell-src-meta-0.8.3.patch";
       sha256 = "1asl932mibr5y057xx8v1a7n3qy87lcnclsfh8pbxq1m3iwjkxy8";
  
positive.code:   xhtml = null;
  
    # Ignore overly restrictive upper version bounds.
    async = doJailbreak super.async;
    cabal-install = doJailbreak super.cabal-install;
    ChasingBottoms = doJailbreak super.ChasingBottoms;
  
negative.code:     sha256 = "0zsgzn0nvdxvqi5z0za3gzlhql2x5d5cr0kkr19j5c67fy177w6b";
    });
  
    # https://github.com/sol/hpack/issues/371
    hpack = appendPatch super.hpack (pkgs.fetchpatch {
      url = "https://gitlab.haskell.org/ghc/head.hackage/raw/master/patches/hpack-0.32.0.patch";
  