Features
* Free and open source
* Easy to setup (just 3 steps)
* Lightweight (the core depends only on servlet-api & commons-io)
* Minification and processing
* Resource merging
* Css url rewriting
* Css variables support (easy integration with css meta framewors future versions)
* Extensible (easy integration with YUICompressor or other similar tools)
* Caching support (easy custom caching strategy integration, default uses a simple HashMap for caching wro4j-extension)
* ...more to come...