Could be an issue. For that reason, the two immutable databases with which I'm familiar (Crux and Datomic[1]) provide operations for removing bits of data from

Could be an issue. For that reason, the two immutable databases with which I'm familiar (Crux and Datomic[1]) provide operations for removing bits of data from history. [1]on-prem, not cloud However even if the DB doesn't offer that operation, you could use "crypto shredding" where you encrypt the data before putting it in the immutable db and then store the key in some kind of mutable store. (Then delete the key when you want to delete its corresponding data). There's also this post which describes some other methods of making a Datomic cloud system gdpr compliant: https://vvvvalvalval.github.io/posts/2018-05-01-making-a-datomic-system-gdpr-compliant.html https://vvvvalvalval.github.io/posts/2018-05-01-making-a-dat...