What should I use to fan out one webhook into multiple systems?

If you want to fan out one webhook to multiple systems, the best tool depends on how much control you need:

Simple options

• Webhook relay / forwarding services
  Good if you just want to duplicate the incoming webhook to several endpoints with minimal setup.
  • Examples: Pipedream, Hookdeck, Svix, Zapier, Make
• Serverless function / small proxy Good if you want basic logic like filtering, transforming, retries, or sending to different destinations.
  • Examples: AWS Lambda, Cloudflare Workers, Google Cloud Functions, Azure Functions

More robust options

• Message queue / event bus Best if reliability matters, you need retries, buffering, scaling, or many downstream consumers.
  • Examples: Kafka, AWS SNS + SQS, Google Pub/Sub, RabbitMQ, NATS

Rule of thumb

• Need quick and easy: use Hookdeck or Pipedream
• Need custom routing/transforms: use a serverless webhook handler
• Need production-grade event fanout: use an event bus / pub-sub system

My recommendation

For most teams, a good starting point is:

1. Receive the webhook
2. Put the event onto a queue or pub-sub topic
3. Let multiple consumers process it independently

That gives you isolation, retries, and easier scaling.

If you want, I can recommend the best option based on your stack (AWS/GCP/Azure, low-code vs code, expected volume, and whether you need retries/idempotency).