Machinery vs pg-boss

Machinery has no write-up on Specifiction yet; its figures are above.

pg-boss is a Node.js job queue that uses PostgreSQL for background processing and asynchronous job execution. It can add a job in the same database transaction as the data change it belongs to, so the job is created only when that transaction commits. Workers use PostgreSQL SKIP LOCKED to claim jobs without blocking one another, with atomic commit safety; delivery is at least once, so a handler may run more than once. Queue controls include priorities, rate limits, debouncing, concurrency policies, retries with exponential backoff, and dead-letter queues. Scheduling covers cron and RRULE, deferral, and dependency-based workflows. Transaction adapters are available for Knex, Kysely, Drizzle, and Prisma. Supported databases include PostgreSQL, CockroachDB, YugabyteDB, Citus, and PGlite. A dashboard can monitor and manage jobs, queues, and schedules, while a JSON HTTP API proxy serves non-Node runtimes. It is MIT-licensed and self-hosted, with a listed price of free. It requires Node 22.12 or higher or Bun, plus PostgreSQL 13 or higher.