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:     # inherit v8
    } // (stdenv.lib.optionalAttrs (!stdenv.isDarwin) {
      inherit http-parser;
    })
    # Node 0.11 has patched c-ares, won't compile with system's version
    // (if unstableVersion then {} else { cares = c-ares; });
  
    sharedConfigureFlags = name: [
      "--shared-${name}"
  
negative.code:     url = "http://nodejs.org/dist/v${version}/node-v${version}.tar.gz";
      sha256 = if unstableVersion
               then "1642zj3sajhqflfhb8fsvy84w9mm85wagm8w8300gydd2q6fkmhm"
               else "0cifd2qhpyrbxx71a4hsagzk24qas8m5zvwcyhx69cz9yhxf404p";
    };
  
    configureFlags = concatMap sharedConfigureFlags (builtins.attrNames deps);
  