Glossary

Event Sourcing

Store the full sequence of state-changing events as the source of truth, deriving current state by replaying them.

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Definition

Store the full sequence of state-changing events as the source of truth, deriving current state by replaying them.

How it works

Instead of overwriting a row, you append immutable events (OrderPlaced, OrderShipped). You get a perfect audit log, time-travel, and the ability to rebuild new read models from history — at the cost of more storage, schema-evolution care, and snapshots so replay stays fast. Often paired with CQRS.

Common questions

What is Event Sourcing?

Store the full sequence of state-changing events as the source of truth, deriving current state by replaying them.

How does Event Sourcing work?

Instead of overwriting a row, you append immutable events (OrderPlaced, OrderShipped). You get a perfect audit log, time-travel, and the ability to rebuild new read models from history — at the cost of more storage, schema-evolution care, and snapshots so replay stays fast.…

What is Event Sourcing used for in system design?

Instead of overwriting a row, you append immutable events (OrderPlaced, OrderShipped). You get a perfect audit log, time-travel, and the ability to rebuild new read models from history — at the cost of more storage, schema-evolution care, and snapshots so replay stays fast.…

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