FuelPHP started out with the goal of adopting the best practices from other frameworks to form a thoroughly modern starting point, which makes full use of PHP Version 5.3 features, such as namespaces. It has little in the way of legacy and compatibility issues that can affect older frameworks.
The framework was started in the year 2010 by Dan Horrigan. He was joined by Phil Sturgeon, Jelmer Schreuder, Harro Verton, and Frank de Jonge. FuelPHP was a break from other frameworks such as CodeIgniter, which was basically still a PHP 4 framework. This break allowed for the creation of a more modern framework for PHP 5.3, and brings together decades of experience of other languages and frameworks, such as Ruby on Rails and Kohana. After a period of community development and testing, Version 1.0 of the FuelPHP framework was released in July 2011. This marked a version ready for use on production sites and the start of the growth of the community.
The community provides periodic releases (at the time of writing, it is up to Version 1.7) with a clear roadmap (http://fuelphp.com/roadmap) of features to be added. This also includes a good guide of progress made to date.
The development of FuelPHP is an open process and all the code is hosted on GitHub at https://github.com/fuel/fuel, and the main core packages can be found in other repositories on the Fuel GitHub account—a full list of these can be found at https://github.com/fuel/.