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EventMachine is a library for Ruby, C , and Java programs. It provides event-driven I/O using the Reactor pattern. EventMachine is designed to simultaneously meet two key needs: * Extremely high scalability, performance and stability for the most demanding production environments; and * An API that eliminates the complexities of high-performance threaded network programming, allowing engineers to concentrate on their application logic. This unique combination makes EventMachine a premier choice for designers of critical networked applications, including web servers and proxies, email and IM production systems, authentication/authorization processors, and many more.