Read Replicas Are NOT CQRS (Stop Confusing This)

Original Description

CQRS isn’t “two databases,” and read replicas aren’t CQRS. CQRS, the Outbox pattern, and Event Sourcing are often called “overengineering,” and I push back with clear definitions and real-world failure modes. We’ll break down why Outbox exists (the dual-write problem), how CQRS is simply separating command and query code paths (even with the same database), and why logging events to ClickHouse/Redshift is analytics, not Event Sourcing. If you’ve heard “outbox is only for finance” or “replicas are enough so CQRS is useless,” this is the nuance people miss.

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0:00 Intro

1:23 Outbox

3:54 CQRS

7:05 Event Sourcing