The pg_embedded_setup_unpriv binary prepares a PostgreSQL installation and
data directory regardless of whether it starts with root privileges. When the
process runs as root it stages directories for nobody and delegates
PostgreSQL lifecycle commands to the worker helper, which executes as the
sandbox user. Unprivileged invocations keep the current identity and provision
directories with the caller’s UID. This guide explains how to configure the
tool and integrate it into automated test flows.