TLDR Data · DEEP DIVES

CHANGE-DATA-CAPTURE DOESN'T SOLVE DUAL-WRITES

aandreakis.com8 min read

Summary from the TLDR Data newsletter

CDC makes downstream writes retryable, ordered, and observable, but it does not make destination systems safe to write twice. The destination still needs durable idempotency or a way to reject duplicates after recovery. This is a useful design-review lens for teams treating CDC as an automatic consistency fix.