Diaa Radwan

Building Event-Driven Systems with PostgreSQL Logical Replication and Drasi

local PDT (Livestream 3)

PostgreSQL's logical replication captures database changes in real-time, but most developers still rely on external streaming platforms like Kafka for event processing. This session shows you how to build event-driven architectures directly on PostgreSQL using its write-ahead log and Drasi, a CNCF Sandbox project that adds continuous queries and filtering on top of change data capture.

You'll see a comparison of three CDC approaches: wal2json with custom consumers, Debezium with Kafka, and Drasi with PostgreSQL. I'll walk through live benchmarks measuring database overhead, end-to-end latency, and lines of code required for each approach. Using a working example, I'll demonstrate how PostgreSQL captures changes, how Drasi filters them with declarative queries, and how to trigger downstream actions—while monitoring PostgreSQL's actual CPU and network usage throughout.

You'll learn when logical replication makes sense for your architecture, how to configure replication slots and publications, how to avoid WAL accumulation issues, and how to choose between different CDC approaches based on your requirements. This session focuses on practical PostgreSQL skills you can apply immediately, whether you're building on Azure, AWS, or on-premises.