Practical guide on how to implement Article 17 of General Data Protection Regulation (GDPR) in the systems using event sourcing pattern.
The event sourcing pattern (which entails storing state as an immutable series of past events rather than just the current state)
has become popular over the past years. How does this affect GDPR compliance?
In event sourcing, the list of past events is (at least conceptually) immutable. This also implies that data can’t be deleted from it, which is exactly what you must be able to do according to article 17’s right to erasure (also known as ‘right to be forgotten’).
How to reconcile this?
The AxonIQ GDPR module ensures that personal data within events is stored in an encrypted form. The encryption keys are automatically generated and are unique to the data subject or the aggregate identifer. The module provides an API to delete this key afterwards. Deletion of this key is equivalent to deleting the personal data fields itself, but doesn’t require any changes to the list of past events. This solves the problem of erasing data in an immutable event list.