wp-background-processing

# WordPress Background Processing > **Model note:** Scaffolding a new Action Scheduler or `WP_Background_Process` implementation is pattern-matching — `haiku` handles it well. Debugging a stuck queue or race condition across async jobs requires reasoning; use `sonnet`. Implement background jobs and queued tasks in WordPress plugins. Three primary tools with distinct trade-offs: Action Scheduler (persistent, battle-tested), `WP_Background_Process` (lightweight, no DB table), WP Cron (built-in, unreliable timing). ## When to use - "Process a large batch of items in the background", "queue a long-running task". - "Set up Action Scheduler", "use WooCommerce queue". - "Implement WP_Background_Process", "chunked batch import". - "Background email sending", "async API calls". - "Fix a WP Cron job not firing", "make scheduled tasks reliable". - "The scheduled action completes but nothing happens", "the handler only runs in the admin". **Not for:** One-off scheduled events (use `wp_schedule_single_event`). REST API async patterns — use `wp-rest-api`. ## Method ### 1. Choose the right tool | Tool | Persistent | Retry | Progress | Requires | Best for | |---|---|---|---|---|---| | Action Scheduler | ✅ DB table | ✅ Configurable | Via hooks | AS or WC | Reliable multi-step queues | | WP_Background_Process | ✅ Options API | ❌ Manual | Via option | ~5KB class | Simple batches, no WC dep | | WP Cron | ❌ (transient) | ❌ | ❌ | Nothing | Maintenance, low-priority tasks | **Rule of thumb...