<div><p>Modern distributed applications must deliver near-realtime performance while simultaneously managing big data and high user loads spread across environments ranging from cloud systems to mobile devices. Unlike traditional enterprise applications which focus on decoupling their internal components by defining programming interfaces, reactive applications go one step further and decouple their components also at runtime. This makes it possible to react effectively and efficiently to failures, varying user demands, and changes in the application's execution environment. The resulting systems are highly concurrent and fault-tolerant, with minimal dependencies among individual system components.</p><p><i>Reactive Design Patterns</i> is a clearly-written guide for building message-driven distributed systems that are resilient, responsive, and elastic. It contains patterns for messaging, flow control, resource management, and concurrency, along with practical issues like test-friendly designs. All patterns include concrete examples using Scala and Akka—in some cases, Java, JavaScript, and Erlang. Software engineers and architects will learn patterns that address day-to-day distributed development problems in a fault-tolerant and scalable way. Project leaders and CTOs will gain a deeper understanding of the reactive design philosophy.</p><p>Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications.</p></div>