Facebook has been developed from the ground up using open source software, and we are proud to give back to the open source community through various open source projects.

Thrift - a framework for scalable cross-language services development. Thrift combines a powerful software stack with a code generation engine to build services that work efficiently and seamlessly between C++, Java, Python, PHP, and Ruby.

phpsh - an open source interactive shell for php that features readline history, tab completion, and quick access to documentation. It was developed at Facebook and ironically, is written mostly in Python. It has been useful for testing the codebase, inspection, and interactive scripting.

Facebook Animation - a Javascript animation library for creating customizable animations using DOM and CSS manipulation

memcached - a distributed memory object caching system. Memcached was not originally developed at Facebook, but we have become the largest user of memcached and actively contribute modifications back to the project. We have contributed substantial changes back to the project, boosting the software's performance by over 20% and increasing its memory efficiency by over 30% while adding new functionality.

Facebook Firefox Toolbar - an extension that adds Facebook functionality to Firefox. This is an example of a client of the Facebook Platform. We are open to accepting patches for future versions - please send them to developers-help@facebook.com. The source code is available here.

Facebook Exporter for iPhoto - a plugin that exports photos from iPhoto directly to Facebook, including captions and tags. This is an example of a client of the Facebook Platform, in particular the photo upload API. We are open to accepting patches for future versions - please send them to developers-help@facebook.com. The source code is available here.

flvtool++ - a tool for hinting and manipulating the metadata of FLV files. It was originally created for our Video project for fast video hinting.

PHPEmbed - In order to make embedding PHP truly simple for all of our developers (and indeed the world) we developed this PHPEmbed library which is just a more accessible and simplified API built on top of the PHP SAPI.

Public Patches Library - A collection of patches that enhance open source projects like PHP, Apache, etc.

Facebook Mirror - A public mirror for projects such as Apache, Linux, Mozilla, GNU, MySQL, and much more...

转自: http://developers.facebook.com/opensource.php