Webhooks

Incoming webhooks (tunnel use case)

The most common use case: expose a local endpoint to receive webhooks from external services.

# Testing Stripe webhooks locally
nullbore open --port 3000 --name stripe-test --ttl 2h
# → https://stripe-test.tunnel.nullbore.com

# Point Stripe's webhook URL at your tunnel
# Stripe → NullBore → localhost:3000/webhooks/stripe

Works with any service that sends webhooks: Stripe, GitHub, Twilio, Slack, Linear, etc.

Tips

Use --idle mode so the tunnel stays alive while you're iterating
Use a named tunnel so the URL is stable across reconnects
The tunnel URL changes if you don't use a name (free tier)

Outgoing webhooks (NullBore events)

Hobby+ plan feature — get notified when tunnel events happen.

NullBore can send webhook notifications when tunnels are created, about to expire, or closed.

Events

Event	Description
`tunnel.created`	A new tunnel was opened
`tunnel.expiring`	Tunnel expires in 5 minutes
`tunnel.closed`	Tunnel was closed (manually or by TTL)

Payload

{
  "event": "tunnel.created",
  "timestamp": "2026-03-30T14:30:00Z",
  "tunnel": {
    "id": "b1d0df1b-...",
    "slug": "myapp",
    "local_port": 3000,
    "ttl": "1h0m0s",
    "expires_at": "2026-03-30T15:30:00Z"
  }
}

Configuration

Configure webhook URLs in the dashboard under Settings → Webhooks.

Status: Outgoing webhooks are coming soon. The event system is designed, implementation is in progress.

NullBore Documentation