Skip to main content
The TypeScript SDK provides a class-based client for Node.js. It sends requests to https://api.signal.apollodeploy.com by default. Before you start, create an API key with Emails: Send permission and verify the From domain.
1

Install the SDK

2

Store your API key

Set SIGNAL_API_KEY in your server environment. Never expose it to browser code.
3

Send an email

to, cc, and bcc are arrays. Your from address must use a domain verified in the same Signal project as the API key.

Production use

  • Reuse the client across requests.
  • Add idempotencyKey when a job may retry the same logical send.
  • Keep the key in a server-side secret manager.
  • Use the returned ID or signed webhooks to follow delivery outcomes.

All SDKs

Compare every supported language and framework.

Manage emails

Understand message states and delivery timelines.