Share a Kafka Topic Only When Order Matters
· 9 min read
We merged Kafka topics because the same services consumed the messages together. It felt simpler. Two incidents showed what we had really done: one shared topic means one shared queue, one failure domain, and one on-call problem—not a tidy folder in a repo.
My default rule: share a topic only when order matters for a clear stream (same partition key, same lifecycle). If urgency, retries, batch vs live traffic, or ownership differ, split the topics. Below I explain why we merged, what broke in production, when one topic is still right, and defaults that help teams avoid the same mistakes.
