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PgQ

The maintained original PgQ event engine, with tick-based batches.

Canonical upstream ↗
API / SDK surfaceSQL · C · Python ecosystem
Inspected snapshotv3.5.2 · source snapshot
Sources checked2026-10-23
License at snapshotISC

View pinned source / version be3d2cee3fc7 · Maintained engine is pgq/pgq. pgq/skytools redirects to archived skytools-legacy, and markokr/skytools labels itself legacy. Do not confuse the engine with NikolayS/PgQue or que-rb/que.

What this system is built around

The maintained original PgQ event engine, with tick-based batches.

A useful starting point

Relevant when batch event-stream consumption and existing PgQ tooling are the required contract. Deployment needs the extension and a ticker/maintenance process; verify managed-provider support.

Editorial fit, based on the cited design. Verify against your workload.

Semantics & operating model

Concise claims with their scope intact. “Not verified” means this review did not establish the answer.

Claiming & concurrency

Qualified

Work is grouped by tick windows and registered-consumer position rather than a per-job running row. Multiple-consumer/cooperative tooling belongs to the surrounding PgQ ecosystem; its full topology was not audited.

Transaction integration

Transactional enqueue

Documented

SQL insert_event inserts into the queue within the caller transaction; snapshot/tick batches track committed event windows.

Transaction integration Transaction integration

Crash recovery & retries

Qualified

An active unfinished batch is returned again by next_batch. event_retry schedules an event at an absolute or relative time. Consumers own processing and when to finish a batch.

Recovery and retries Recovery and retries

Delayed & recurring work

Not verified

event_retry supports future redelivery times. No current first-class per-job cron API was verified in the engine sources reviewed.

Recovery and retries

Uniqueness / deduplication

Not verified

No general unique-job producer API was verified. event_retry handles repeated retry insertion idempotently, which is a narrower operation.

Uniqueness scope

Postgres extension required

Required

PgQ is a PostgreSQL extension with C low-level functions. pgqd is a separate maintenance/ticker daemon. Current engine README lists PostgreSQL 10–19.

Installation and prerequisites Installation and prerequisites Installation and prerequisites

Operator interface

Not verified

No current official operations UI was verified in the reviewed engine and daemon documentation.

Installation and prerequisites

Tradeoffs to carry into a test