Overview

aSaaSin uses Resend for sending transactional emails (password reset, login notifications) and managing newsletter subscribers.

Create an account & API key

  1. Go to Resend and create a free account.
  2. In the Dashboard → API Keys, generate a new API key.
  3. Copy the key and add it to your .env file as RESEND_API_KEY.
  4. In Emails → Audiences, create a new audience list for your newsletter subscribers.
  5. Copy the Audience ID and set it as RESEND_AUDIENCE_ID.
  6. Under Settings → Domains, verify your sending domain and choose the sender address you want to use as RESEND_NOTIFICATION_EMAIL.

Domain verification can take some time depending on your DNS provider. You can still test emails using the default Resend domain before your own domain is verified.

Add to env

# Resend
RESEND_API_KEY=
RESEND_AUDIENCE_ID=
RESEND_NOTIFICATION_EMAIL=

Save the file, then restart the dev server if it was running.

What each key is for

  • RESEND_API_KEY — Main API key for authenticating with the Resend API.
  • RESEND_AUDIENCE_ID — Audience list ID used for newsletter signups and email campaigns.
  • RESEND_NOTIFICATION_EMAIL — Default sender email used for transactional notifications.