anchor.diff: -{ stdenv, fetchurl, openssl, python, zlib, v8, utillinux, http-parser, c-ares
  +{ stdenv, fetchurl, openssl, python, zlib, v8, utillinux, http-parser
   , pkgconfig, runCommand, which, unstableVersion ? false 
   }:
   
  
positive.code:     ln -sv /usr/sbin/dtrace $out/bin
    '';
  
    version = if unstableVersion then "0.11.13" else "0.10.33";
  
    # !!! Should we also do shared libuv?
    deps = {
  
negative.code:     # inherit v8
    } // (stdenv.lib.optionalAttrs (!stdenv.isDarwin) {
      inherit http-parser;
    });
  
    sharedConfigureFlags = name: [
      "--shared-${name}"
  