DynamoDB Streams
AWS feature: DynamoDB exposes a change log (insert/modify/remove) as a stream. Use: event-driven architecture, trigger Lambda on data change, sync to another store (OpenSearch, Redshift), audit log.
Records stored 24h, polled via Kinesis API or directly via Lambda triggers. Per-shard ordering preserved. NEW_AND_OLD_IMAGES mode contains before and after state. AWS DynamoDB Streams + Lambda is CDC replication — most used pair in the AWS stack. Kinesis Data Streams is similar but separate (costs more, more features). Pricing: free up to 24h retention, Lambda invocations are what you pay for.