Automation library · Alerts and monitoring

Build an event-driven pub/sub bus with HTTP and Slack

Started by another system calling it, and works across Slack. 23 steps, 4 branches, 1 loop or waits: large, and worth reading before you trust it with anything live.

Large

Download free
23 stepsLarge: read it before trusting it with anything live
4Branches: places the flow splits
1Loop or waits
1Service it connects to

The flow

Starts it 4Logic 12Service 7

The steps in the order they run, from what starts it.

  1. 1Event Ingress - WebhookWebhookStarts it
  2. 2Event Ingress - Execute Workflow TriggerExecute Workflow triggerStarts it
  3. 3Merge - Ingress SourcesMergeLogic
  4. 4Set - Event Bus ConfigSetLogic
  5. 5Code 1 - Validate & Enrich EnvelopeCodeLogic
  6. 6IF - Envelope ValidIfLogic
  7. 7HTTP Request - Append to Event StoreHttp RequestService
  8. 8Respond - Invalid EnvelopeRespond To WebhookStarts it
  9. 9Respond - Event AcceptedRespond To WebhookStarts it
  10. 10Switch - Route by Event TypeSwitchLogic
  11. 11Subscriber - Order ServiceHttp RequestService
  12. 12Subscriber - Notification ServiceHttp RequestService
  13. 13Code - Unknown Event TypeCodeLogic
  14. 14Merge - Subscriber ResultsMergeLogic
  15. 15Subscriber - Analytics ServiceHttp RequestService
  16. 16Code - Tag Subscriber & OutcomeCodeLogic
  17. 17IF - Delivery FailedIfLogic
  18. 18Code - Compute Backoff & Retry CountCodeLogic
  19. 19HTTP Request - Ack Event StoreHttp RequestService
  20. 20IF - Attempts ExhaustedIfLogic
  21. 21HTTP Request - Write to Dead Letter QueueHttp RequestService
  22. 22Wait - Exponential BackoffWaitLogic
  23. 23Slack - DLQ AlertSlackService

How it's built

Starts on
Another system calling it
Steps
23, with 4 branches, 1 loop or waits
Size
Large: read it before trusting it with anything live
Connects to
Slack
Model
None. This is plumbing, not judgement

Questions

What does it need to run?

An n8n account, plus your own Slack account. You connect your own accounts after importing it; none are included.

What starts it?

It starts on another system calling it.

Does it use AI?

No. Every step is fixed logic or a call to a service, so it does the same thing every time.

How long does it take to set up?

Take your time. At 23 steps it is large: read it before trusting it with anything live.

How do I import it?

Copy the workflow, open a new workflow in n8n and paste. The steps appear on the canvas, ready for your own accounts.

Before you run it

Nothing here has been tested by us. It is somebody's working automation, read and described from its own steps. Treat the connections it wants as a list of accounts it will touch, and read the 23 steps before you point it at anything that matters.