Async Patterns

Queues, fan-out, retries, webhooks: when and why to decouple work from the request path.

1. 1
   Instagram FeedIntermediate

   Fan-out on write vs read, ranking, CDN.
   →
2. 2
   WhatsAppAdvanced

   Persistent connections, message queues, delivery.
   →
3. 3
   Payment GatewayAdvanced

   Idempotency, fraud, async webhooks, ledger.
   →