Comment by em3s

You might be right! Kafka + KV store + Redis can definitely work for this.

Our teams typically started with MySQL, then added Kafka and Redis as they scaled. The pain wasn't the initial build—it was what happened after: every team implemented forward/reverse lists, counts, and indexes slightly differently. Retries and out-of-order events caused subtle drift. Migrations became error-prone because the "rules" for derived data lived in application code scattered across services.

That's what Actionbase does: versioned state transitions, pre-computed indexes, idempotent mutations—all in one place. If your current setup is working and correctness isn't drifting, you probably don't need this.

I wrote more about this trade-off in https://github.com/kakao/actionbase/discussions/32 —genuinely asking whether we overbuilt.