I was looking into this
https://postgres.ai/docs/database-lab/masking
and was searching how to mask (dynamically) my data using Amazon RDS PostgreSQL, but couldn't find any real solution.
Is there any one out there that solved that without recurring to server/backend masking?
If you want to retrieve readonly masked data I'd say to use views from the PostgreSQL. One way to achieve that would be:
SET search_path TO '$user', masked, public
This way, if you make a query to select from the said table, it'll first look for the masked schema and if it has a view with the same name as the table you are doing your query, it'll retrieve the masked data from the rules applied to the view.