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Apache REEF&trade; - a `stdlib` for Big Data
=============================================
Apache REEF&trade; (Retainable Evaluator Execution Framework) is a  library for developing portable applications for cluster resource managers such as [Apache Hadoop&trade; YARN][YARN] or [Apache Mesos&trade;][Mesos]. Apache REEF drastically simplifies development of those resource managers through the following features:

Features
--------
 * **Centralized Control Flow:** Apache REEF turns the chaos of a distributed application into events in a single machine, the Job Driver. Events include container allocation, Task launch, completion and failure. For failures, Apache REEF makes every effort of making the actual `Exception` thrown by the Task available to the Driver.
 * **Task runtime:** Apache REEF provides a Task runtime called Evaluator. Evaluators are instantiated in every container of a REEF application. Evaluators can keep data in memory in between Tasks, which enables efficient pipelines on REEF.
 * **Support for multiple resource managers:** Apache REEF applications are portable to any supported resource manager with minimal effort. Further, new resource managers are easy to support in REEF. 
 * **.NET and Java API:** Apache REEF is the only API to write YARN or Mesos applications in .NET. Further, a single REEF application is free to mix and match Tasks written for .NET or Java.
 * **Plugins:** Apache REEF allows for plugins (called "Services") to augment its feature set without adding bloat to the core. REEF includes many Services, such as a name-based communications between Tasks, MPI-inspired group communications (`Broadcast`, `Reduce`, `Gather`, ...) and data ingress.   

REEF @ Apache Big Data 2016
---------------------------

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Latest Release
--------------
The latest release of Apache REEF is ${currentStableVersion}. Please go to the [downloads] page to find out more.

[YARN]: https://hadoop.apache.org/docs/current/hadoop-yarn/hadoop-yarn-site/YARN.html
[Mesos]: https://mesos.apache.org/
[downloads]: downloads.html