Facebook has been developed from the ground up using open source software. Developers building with Platform scale their own applications using many of the same infrastructure technologies that power Facebook.
Platform
Platform engineering team has released and maintains open source SDKs for Android, C#, iPhone, JavaScript, PHP, and Python.
Developer tools codemod assists with large-scale codebase refactors that can be partially automated but still require human oversight and occasional intervention.
Facebook Animation is a JavaScript library for creating customizable animations using DOM and CSS manipulation. flvtool++ is a tool for hinting and manipulating the metadata of FLV files. It was originally created for Facebook Video.
Online Schema Change for MySQL lets you alter large database tables without taking your cluster offline.
Phabricator is a collection of web applications which make it easier to write, review, and share source code. It is currently available as an early release and is used by hundreds of Facebook engineers every day.
PHPEmbed makes 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. phpsh provides an interactive shell for PHP that features readline history, tab completion, and quick access to documentation. It is ironically written mostly in Python.
Three20 is an Objective-C library for iPhone developers which provides many UI elements and data helpers behind our iPhone application. XHP is a PHP extension which augments the syntax of the language such that XML document fragments become valid expressions.
XHProf is a function-level hierarchical profiler for PHP with a simple HTML-based navigational interface.
Infrastructure
Apache Cassandra is a distributed storage system for managing structured data that is designed to scale to a very large size across many commodity servers, with no single point of failure.
Apache Hive is data warehouse infrastructure built on top of Hadoop that provides tools to enable easy data summarization, adhoc querying and analysis of large datasets.
FlashCache is a general purpose writeback block cache for Linux. It was developed as a loadable Linux kernel module, using the Device Mapper and sits below the filesystem.
HipHop for PHP transforms PHP source code into highly optimized C++. HipHop offers large performance gains and was developed over the past two years.
Open Compute Project an open hardware project aims to accelerate data center and server innovation while increasing computing efficiency through collaboration on relevant best practices and technical specifications.
Scribe is a scalable service for aggregating log data streamed in real time from a large number of servers.
Thrift provides a framework for scalable cross-language services development in C++, Java, Python, PHP, and Ruby.
Tornado is a relatively simple, non-blocking web server framework written in Python. It is designed to handle thousands of simultaneous connections, making it ideal for real-time Web services.
Mirror
Hosts public mirror for projects such as Apache, Centos, CPAN, Fedora, GNU, Mozilla, MySQL, and much more...
Core Concepts
Social Plugins
Social Plugins enable you to provide engaging social experiences to your users with just a line of HTML. Because the plugins are served by Facebook, the content is personalized to the viewer whether or not they have signed into your site.
Graph API
The Graph API is the core of Facebook Platform, enabling you to read and write data to Facebook. It provides a simple and consistent view of the social graph, uniformly representing objects (like people, photos, events, and pages) and the connections between them (friendships, likes, and photo tags).
Social Channels
Facebook Platform lets you integrate with social channels such as News Feed and Requests to help you drive growth and engagement with your app, site or content.
Authentication
Facebook authentication enables your app to interact with the Graph API on behalf of Facebook users and provides a powerful single-sign on mechanism across Web, mobile, and desktop apps.
Open Graph protocol
The Open Graph protocol enables you to integrate your pages into the social graph. These pages gain the functionality of other graph objects including profile links and stream updates for connected users.