Postgres's LISTEN and NOTIFY as a surefold Stream: one connection, notifications in commit order.

Durable jobs on Postgres, enqueued in the caller's own transaction so they commit with its change.

A surefold-cache told by Postgres NOTIFY that a row changed: a payload drops its key, a gap every key.

Feature flags per tenant from a Postgres table, read under its row-level security policy, for OpenFeature.