event sourcing
compound.compound. a way of storing data where you keep a list of every change that happens instead of just the current state. It is like a bank statement that shows every transaction rather than just your final balance.
compound. an architectural pattern in which state changes are captured as a sequence of immutable events. Instead of overwriting the current state in a database, the system persists the full history of transitions to allow for reconstruction and auditing.
The bank uses event sourcing to track every deposit and withdrawal.
By implementing event sourcing, the development team could easily debug the system by replaying the exact sequence of actions that led to the error.
In high-compliance industries, event sourcing provides an inherent audit log, ensuring that the provenance of every data point is preserved and verifiable against the historical record of state transitions.
A compositional term formed from the noun event, denoting a discrete occurrence, and the gerund sourcing, in the sense of identifying a point of origin. It emerged within the domain of enterprise software architecture to distinguish the practice from state-based persistence.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.
Commonly used in software engineering and distributed systems; often paired with the CQRS pattern.
Last updated July 22, 2026