Event-Driven Architecture on a Budget: Kotlin Coroutines + Redis Streams

What We Will Build Today we are building a lightweight event-driven pipeline using Kotlin coroutines and Redis Streams. By the end, you will have a working producer that buffers and batches events, a consumer built on Kotlin Flows, and a clean abstraction layer that lets you swap in Kafka later without rewriting your application. Let me show you a pattern I use in every project that needs async event processing without the operational weight of a full Kafka cluster. Prerequisites Kotlin 1.9+ with coroutines ( kotlinx-coroutines-core ) A running Redis 6.2+ instance (Docker works fine: docker run -p 6379:6379 redis:7 ) Lettuce Redis client with coroutine support ( lettuce-core ) Basic familiarity with Kotlin coroutines and Flow Step 1: Build the Buffered Producer The producer uses a Kotlin Channel for local backpressure, then flushes events to Redis Streams in batches. class EventProducer ( private val redis : RedisCoroutinesCommands < String , String >, private val stream : String , buf