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How do you fan out a webhook to many destinations?

Fanning out a webhook means delivering one inbound event to N destinations, each with its own transform, its own filter, its own retry pipeline, and its own dead-letter queue. In Slashbin, one slow or downed destination never blocks the others — per-destination fault isolation is a contract of the platform, not something you build.

How it works in Slashbin

  1. Validate once at the edge. The inbound payload is checked against your Golden Model a single time — drift is rejected before any destination sees it.
  2. Each destination runs its own pipeline. Filter, transform to its Destination Model, deliver, retry, DLQ — all independent per destination.
  3. Failures are isolated. A destination that starts timing out gets its own circuit breaker and its own backoff. Deliveries to every other destination continue normally.
  4. Replay works per destination. When a destination recovers, replay its DLQ in isolation — no risk of double-delivering to destinations that were fine the whole time.

When you need it

Multi-tool workflow

One order webhook feeds your CRM, your warehouse, and your analytics — each expects a different shape and has its own reliability profile.

Environment splits

Production and staging both need the same events, filtered differently, without one env's traffic contaminating the other's.

Adding a destination shouldn't be a deploy

Marketing wants Klaviyo, sales wants Slack alerts. Both are configuration in the gateway, not new code paths in your handler.

Fan-out at the gateway vs in your handler

ApproachWhat breaks
Fan out inside your webhook handlerOne slow destination holds the request open, others time out, the vendor retries the whole webhook, and now everyone sees duplicates.
Fan out via a message queue you ownYou now own consumers, retries, backoff, DLQs, and a runbook per destination — plus every schema change is a coordinated deploy.
Fan out at the Slashbin gatewayEvery destination is a configured pipeline with its own retries, its own DLQ, and its own filter. Adding a destination is configuration.

Feature detail

Per-Destination Fault Isolation

One destination failing never blocks or throttles another — every destination has its own retry queue and circuit breaker.

Per-Destination Filters

Route by rule — send subscription orders to your CRM only, test-tagged orders to staging, everything else to production.

Per-Destination Transforms

Each destination gets its own Destination Model derived from the Golden Model, so downstream shapes are decoupled from the source.

Independent DLQs

Terminal failures land in a dead-letter queue scoped to the destination — replay one destination without touching the others.

Deep dive

Learn how fan-out routing works in Slashbin.

View Setup Guides