I began a new project recently that will replace an existing web application written using a heavy-weight Model View Controller (MVC) framework with a much lighter solution, which will be built around a light-weight "micro" framework.
The only mandated requirements I had for choosing this framework is that it be simple to use and robust, and be implemented in PHP. As you may already know, I am the developer of the Alpha Framework which is a heavy-weight full-stack PHP MVC framework, so the micro framework approach is something of a new departure for me.
I must admit to being very impressed with the work that is being carried out in this area by many talented PHP developers. If anything, the difficulty I had in choosing a suitable micro framework for our needs is that there are too many options.
In the end, I have chosen Silex due to the following reasons:
While I am still a big fan of the full-stack approach of frameworks like Alpha, I also believe that for some projects a micro framework like Silex has a lot to offer, and I look forward to using this framework on our new project in the months ahead.
Updated 2022 : note that the above post was originally published in 2012, but is left here for archival purposes. It seems the Silex framework is now dead, so I have unlinked it above.