SignalWire

Signature Verification

Property	Value
Algorithm	HMAC-SHA256 and HMAC-SHA1 (Twilio-compatible)
Headers (priority order)	X-SignalWire-Signature, X-Twilio-Signature, X-SignalWire-SHA256-Signature, X-Twilio-SHA256-Signature

SHA1 signing formula (primary):

Base64(HMAC-SHA1(url + sorted_params, auth_token))

SHA256 signing formula (variant):

Base64(HMAC-SHA256(url + sorted_params, secret))

Transyt checks headers in priority order, preferring SignalWire-specific headers over Twilio-compatible fallbacks. Both SHA1 and SHA256 variants are supported.

Setup

1. In your SignalWire Space, navigate to your phone number or LaML application settings
2. Set the webhook URL to:

   https://ingest.transyt.com/signalwire/{your-account-slug}

3. Use your SignalWire Auth Token as the signing secret when creating the account

Note

SignalWire uses Twilio-compatible signature verification. If you’re migrating from Twilio, the same signing approach works with both providers.

Account Configuration

curl -X POST https://ingest.transyt.com/admin/accounts \
  -H "X-Admin-Token: YOUR_ADMIN_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{
    "provider": "signalwire",
    "account_slug": "main-account",
    "app_key": "my-app",
    "signing_secret_current": "your-signalwire-auth-token"
  }'

Event Type Mappings

SMS Events

SignalWire Status	Transyt Event
received	sms.inbound
delivered	sms.delivered
sent	sms.sent
failed	sms.failed
undelivered	sms.undelivered

Voice Events

SignalWire Status	Transyt Event
initiated	call.initiated
ringing	call.ringing
answered	call.answered
completed	call.completed
busy	call.busy
no-answer	call.no_answer
failed	call.failed

Fax Events

SignalWire Status	Transyt Event
fax.received	fax.inbound
fax.sent	fax.sent
fax.failed	fax.failed

External ID

The external ID is a composite of the SID and status: {MessageSid}:{status}, {CallSid}:{status}, or {FaxSid}:{status}. This ensures each status change for the same resource is stored as a separate event.