anchor.diff:  
   , keyutils
   , libaio
  -, libnih
   , libscrypt
   , libsodium
   , liburcu
  
positive.code: }:
  
  let
    date = "2019-01-14";
    rev = "8630059e6ac363bea39e54df3f8115da5a5c2c5d";
  in
  stdenv.mkDerivation {
    name = "bcachefs-tools-${date}";
  
negative.code:   src = fetchzip {
      version = 6;
      url = "https://evilpiepirate.org/git/bcachefs-tools.git/snapshot/bcachefs-tools-${rev}.tar.xz";
      multihash = "QmW94u4GrnLMKKvL6PLBFEDP8jQeDgvC42oxTJrZFy237V";
      sha256 = "d62d6cc9d869a926e6f64b5fa09d0063cd78050ca0df1ab5b92244528f9b912a";
    };
  
    buildInputs = [
      keyutils
      libaio
      libscrypt
      libsodium
      liburcu
  