Postgres LISTEN/NOTIFY suffers a global exclusive lock on NOTIFY calls, which serializes commits and caps throughput around 2.9K writes/sec. By buffering notifications in memory and flushing them in batched transactions—plus a low-frequency polling fallback—the stream writer can leverage group commits and hit 60K writes/sec with 15–100ms latency.

Stash is an open-source service that adds continuous memory to any AI model by storing and organizing session data in PostgreSQL with pgvector. It transforms raw conversations into structured facts, relationships, and patterns, so agents recall preferences, avoid repeated errors, and track long-term goals. Integration via MCP makes it model-agnostic, self-hostable, and free of vendor lock-in.

PgQue is a pure SQL/PLpgSQL event queue for Postgres 14+ that delivers durable, Kafka-style streams without dead tuples or external daemons. It uses snapshot-based batching and TRUNCATE-driven table rotation for stable performance under sustained load. A pg_cron (or any scheduler) ticker drives 1–2 second end-to-end delivery.