Atom is a PHP 5.3 component-based library that aims to extend PHP, not abstract it. It focuses on security, scalability, optimization and simplicity, while solving problems intrinsic to any application. The Atom code-base is highly organized and continuously optimized to ensure it can deliver powerful results with as small a footprint as possible.
Atom's design focuses on scalability challenges by extending PHP's power as opposed to abstracting it away. It was built on the assumption that PHP provides a powerful foundation for development, so Atom capitalizes on that power where it makes the most sense.
Atom is not for your everyday, "do it for me" developer. It's built for the "get your hands dirty" developers out there. The kind of coders who want to know why code works, not simply that it works. A lot of thought work is put into each line of code inside of Atom. Each class will require an understanding of design patterns, the way PHP works, and even how your server interacts with your code. Atom may require you to learn a few things you didn't know... and we hope Atom can benefit from a few things you know that it doesn't.
For these reasons, Atom might not be the best library choice for your project. You might prefer other frameworks that take care of a lot of the thinking for you. However, there's a lot of interesting stuff baked right into the heart of Atom, especially if you like the idea of working with code that's fundamentally based around giving you more bang for your bit.
Our library delivers a great deal of power with a very small footprint. Even if you don't adopt the library, it may be useful to understand how it is built, and what lead to those decisions. We hope you can learn from Atom, and in turn, can help us make Atom even better.
You can download Atom from GitHub in either zip or tar formats.
You can also clone the project with Git by running:
$ git clone git://github.com/atomphp/atom