PostgreSQL is a pretty mature, reliable piece of kit. Audit logs in a financial sense are generally a matter of extreme importance and are not performance-sensitive on the read side.
Conservatism is the watchword when $$$ are involved.
We have a few different types of auditing information. At that point in the timeline, it was all in PostgreSQL. Today, we keep only the critical auditing information in the main database.
Conservatism is the watchword when $$$ are involved.