Every relevant action is logged: who, when, from where and the before-and-after values.
The activity log records every relevant action in the system: who did it, when, from which IP and device, on which entity, the action and the before-and-after values in JSON, and through which channel (panel, portal, API or cron).
It is read-only, with a filterable viewer and CSV export. In addition, invoicing keeps its own system event log (SIF) compliant with the VeriFactu regulation, and there is a technical error log with rotation.