When we launched Campayn, we started with CakePHP, one of the oldest PHP frameworks. We started with the first version and have moved onto 2.1. CakePHP just moved into 3.x which requires a huge rewrite so we haven't used that yet. They still support 2.1 so that’s great. They are a great team that writes great code. We contribute back to the project to thank them for keeping their code open source.