Webhooks vs Polling
Polling is the client asking on a schedule; a webhook is the server calling the client. The trade is between latency, load, and delivery guarantees. This video follows both patterns over time, showing what each side must store, what happens when the receiver is down, and why webhooks are at-least-once at best.
Topics covered:
- Polling: the client's schedule, the server's load
- Webhooks: the server making an HTTP call to the client
- Delivery guarantees: at-least-once and retry schedules
- Signatures and verification: proving the request is real
- The failure mode: receiver down, events lost or replayed
- When each wins: fire-and-forget vs guaranteed delivery
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