anchor.diff:  
   in {
   
  -  idea_community = buildIdea rec {
  +  idea-community = buildIdea rec {
       name = "idea-community-${version}";
  -    version = "13.1.3";
  -    build = "IC-135.909";
  -    description = "IntelliJ IDEA 13 Community Edition";
  +    version = "13.1.4b";
  +    build = "IC-135.1230";
  +    description = "Integrated Development Environment (IDE) by Jetbrains, community edition";
  +    longDescription = ''
  +      Lightweight IDE for Java SE, Groovy & Scala development
  +      Powerful environment for building Google Android apps
  +      Integration with JUnit, TestNG, popular SCMs, Ant & Maven
  +      Free, open-source, Apache 2 licensed.
  +    '';
       license = stdenv.lib.licenses.asl20;
       src = fetchurl {
         url = "http://download-ln.jetbrains.com/idea/ideaIC-${version}.tar.gz";
  -      sha256 = "62ed937ef68df16eef4d32772b6510835527f95020db1c76643f17ed2c067b51";
  +      sha256 = "8b4ee25fd2934e06b87230b50e1474183ed4b331c1626a7fee69b96294d9616d";
       };
     };
   
  -  idea_ultimate = buildIdea rec {
  +  idea-ultimate = buildIdea rec {
       name = "idea-ultimate-${version}";
  -    version = "13.1.3";
  -    build = "IU-135.909";
  -    description = "IntelliJ IDEA 13 Ultimate Edition";
  +    version = "13.1.4b";
  +    build = "IU-135.1230";
  +    description = "Integrated Development Environment (IDE) by Jetbrains, requires paid license";
  +    longDescription = ''
  +      Full-featured IDE for JVM-based and polyglot development
  +      Java EE, Spring/Hibernate and other technologies support
  +      Deployment and debugging with most application servers
  +      Duplicate code search, dependency structure matrix, etc.
  +    '';
       license = stdenv.lib.licenses.unfree;
       src = fetchurl {
         url = "http://download-ln.jetbrains.com/idea/ideaIU-${version}.tar.gz";
  -      sha256 = "6d99e49a63a197e19381a85535ab424a7832653db8cceb3bca7d53615ec7a53d";
  +      sha256 = "84660d97c9c3e4e7cfd6c2708f4685dc7322157f1e1c2888feac64df119f0606";
       };
     };
   
  
positive.code:     meta = {
        homepage = http://www.jetbrains.com/idea/;
        inherit description;
        inherit license;
        maintainers = [ stdenv.lib.maintainers.edwtjo ];
        platforms = stdenv.lib.platforms.linux;
  
negative.code: let
  
    buildIdea =
    { name, version, build, src, description, longDescription, license }:
  
    stdenv.mkDerivation rec {
      inherit name build src;
  