What does CI not do for you?

[eluser]n0xie[/eluser]
You have to build most of the libraries yourself (which can be considered a good thing). As long as you remember to write them in a way that can integrate easily in new projects, you should be able to build your own extensive library of libraries. There really isn't much you can't do with CodeIgniter since it's basically plain PHP with a router and an easy db connector.