Reactor Core

Reactor Core is a reactive programming library for building non-blocking applications on the JVM, implementing the Reactive Streams specification. It provides a foundational API for reactive streams using the Publisher-Subscriber model, with key types like Mono (for 0-1 elements) and Flux (for 0-N elements). It enables efficient, asynchronous data processing with backpressure support to prevent overwhelming consumers.

Also known as: Reactor, Project Reactor, Reactor 3, Reactor Library, Reactor JVM

Why learn Reactor Core?

Developers should learn Reactor Core when building high-performance, scalable applications that require handling streams of data asynchronously, such as microservices, real-time data processing, or event-driven systems. It's essential for use cases like reactive web applications with Spring WebFlux, IoT data streams, or financial trading platforms where low latency and resource efficiency are critical.

Learning Resources

• docs: Reactor Core Reference Guide
• tutorial: Reactive Programming with Reactor 3 - Baeldung
• video: Reactor 3 Workshop - InfoQ
• course: Hands-On Reactive Programming with Reactor - Coursera
• book: Reactive Spring - O'Reilly Book