Combining a PII Catalog with Postgres Binary Protocol Proxying

The query hit the database, but you never saw the sensitive data.

That is the point of combining a PII catalog with Postgres binary protocol proxying. It lets you inspect and control data flows at the protocol level without breaking application compatibility. You capture, mask, or block fields that contain personally identifiable information while still serving normal client requests at full speed.

Postgres uses a binary protocol for prepared statements and result sets. This protocol is efficient, but it makes PII inspection harder than with simple text-based queries. A proxy that speaks the Postgres binary protocol can read and parse messages between client and server in real time. It can match columns against a prebuilt PII catalog and apply the right policy before the data leaves the database.

The PII catalog is the map. It defines which tables and columns contain sensitive values like names, emails, government IDs, or payment details. It should be versioned, queryable, and easy to extend as data models change. The proxy uses this catalog to decide what to redact, encrypt, or audit without having to inspect application code or change ORM settings.

Building this kind of Postgres binary protocol proxy means dealing with message framing, parameter formats, and row description metadata. Once implemented, it allows centralized enforcement of compliance rules, observability into PII queries, and integration with monitoring and alerting systems. Because the logic is outside the database engine, you avoid custom extensions or forks that are hard to maintain.

Done right, this approach lowers risk and increases control. It satisfies regulatory requirements while keeping latency minimal and deployment straightforward. You gain the power to intercept access to sensitive data with precision, without rewriting client applications or database schemas.

See how this works live in minutes—try it now at hoop.dev.