symfony-scheduler_skill

Overview

This skill helps implement resilient asynchronous workflows for Symfony Scheduler, focusing on idempotency, retries, and operational visibility. It provides guidance to update async contracts, handlers, and retry/failure policies to operate reliably under at-least-once delivery. The result is a hardened scheduler setup with clear operational controls and validation steps.

How this skill works

The skill inspects your async contract, delivery semantics, and handler implementations to identify non-determinism and side effects. It recommends idempotency patterns, routing and retry configuration for Symfony Messenger/Scheduler, and a failure transport strategy. It also defines observable signals and validation steps to prove safe replay and recovery.

When to use it

• Building or refactoring Symfony async tasks backed by Messenger/Scheduler
• Stabilizing systems that experience duplicate deliveries or flaky retries
• Defining operational controls for scheduled jobs and failure transports
• Preparing systems for safe replays or disaster recovery testing

Best practices

• Assume at-least-once delivery; design handlers to tolerate duplicates and partial runs
• Make handlers idempotent by using dedup keys, versioned state, or transactional checkpoints
• Keep handlers deterministic: avoid non-repeatable external calls without compensation
• Centralize retry and failure transport policies; treat poison messages explicitly
• Add observability: structured logs, metrics for retries/poisons, and replay audit trails

Example use cases

• Convert scheduler tasks that mutate external systems into idempotent command handlers with dedup keys
• Configure Messenger retry and failure transport with clear escalation paths for human review
• Validate replay scenarios by running recorded inputs against handlers in a sandbox and asserting idempotent outcomes
• Instrument scheduler jobs to emit retry and failure metrics and integrate with alerting
• Implement a poison-message handler that quarantines and annotates failed payloads for manual triage