anchor.diff:  
     nativeBuildInputs = [ pkgconfig ];
     buildInputs = [
  -    nettools gettext readline openssl python flex ncurses sqlite postgresql
  +    nettools gettext readline openssl python2 flex ncurses sqlite postgresql
       libmysql zlib lzo jansson acl glusterfs libceph libcap rocksdb
     ];
   
  
positive.code: { stdenv, fetchFromGitHub, pkgconfig, nettools, gettext, libtool, flex
  , readline ? null, openssl ? null, python ? null, ncurses ? null, rocksdb
  , sqlite ? null, postgresql ? null, libmysql ? null, zlib ? null, lzo ? null
  , jansson ? null, acl ? null, glusterfs ? null, libceph ? null, libcap ? null
  }:
  
negative.code:     "--enable-sql-pooling"
      "--enable-scsi-crypto"
    ] ++ optionals (readline != null) [ "--disable-conio" "--enable-readline" "--with-readline=${readline.dev}" ]
      ++ optional (python2 != null) "--with-python=${python2}"
      ++ optional (openssl != null) "--with-openssl=${openssl.dev}"
      ++ optional (sqlite != null) "--with-sqlite3=${sqlite.dev}"
      ++ optional (postgresql != null) "--with-postgresql=${postgresql}"
  