anchor.diff:  
   
   let
  -  version = "2.4.0";
  -  sha256 = "02baa90f04da41e04b6c18eedfda53110c45ae943d4e65050f6d202f7de07d29";
  +  version = "2.4.3";
  +  sha256 = "1fg4pmla5m903m76ndjd8q5dkcykf67v1p4dcajmnr3bvg2p8lza";
   in stdenv.mkDerivation rec {
     name = "postgis-${version}";
   
  
positive.code:     inherit sha256;
    };
  
    # don't pass these vars to the builder
    removeAttrs = ["sql_comments" "sql_srcs"];
  
    # create aliases for all commands adding version information
    postInstall = ''
  
negative.code: { fetchurl
  , fetchpatch
  , stdenv
  , perl
  , libxml2
  