> ## Documentation Index
> Fetch the complete documentation index at: https://docs.usesend.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Changelog

> Product updates and announcements from Unsend

<Update label="March 2026" description="v1.9.0">
  ### Campaign Personalization with Contact Books

  Campaigns now support contact-book variables for personalization, so you can tailor each message with richer subscriber data.

  ### Double Opt-In Customization

  Double opt-in now supports customizable confirmation flows and copy, making it easier to match your onboarding experience and compliance requirements.

  ### API and SDK Coverage

  Contact book support has been expanded in the SDK, dashboard analytics is now available in both the public API and SDK, and a public endpoint to delete campaigns has been added.

  ### Webhook Filtering by Domain

  Webhooks now support multi-domain filtering, making it easier to route, monitor, and manage events across different projects.
</Update>

<Update label="February 2025" description="v1.8.0">
  <Frame>
    <img src="https://mintcdn.com/ossapps/fpRnVe9he7fa4B0M/images/changelog/webhook.png?fit=max&auto=format&n=fpRnVe9he7fa4B0M&q=85&s=d46a231801cd0f5e5b1b277c47b781a7" alt="Schedule Campaigns" width="2808" height="1654" data-path="images/changelog/webhook.png" />
  </Frame>

  ### Webhooks

  You can now receive real-time notifications for email events via webhooks. Configure webhook endpoints to track deliveries, bounces, complaints, and more. [Learn more](https://docs.usesend.com/guides/webhooks)

  ### Contact Books API

  Manage your contact books programmatically with the new public API. Create, update, and organize contacts at scale.

  ### Idempotency Support

  API requests now support idempotency keys, ensuring safe retries without duplicate sends.

  ### Other improvements

  * Export contact books to CSV for offline use.
  * Security fixes for CVE-2025-55184 and CVE-2025-55183.
  * Various bug fixes and performance improvements.
</Update>

<Update label="October 2024" description="v1.7.0">
  <Frame>
    <img src="https://mintcdn.com/ossapps/IRky_28zjbUDKDwj/images/changelog/schedule-campaign.png?fit=max&auto=format&n=IRky_28zjbUDKDwj&q=85&s=c796748060c400fc0090e6e335c50d4e" alt="Schedule Campaigns" width="1608" height="940" data-path="images/changelog/schedule-campaign.png" />
  </Frame>

  ### Schedule Campaigns

  You can now Schedule campaigns with natural language like "tomorrow at 9am" or "next Monday at 10am".

  ### Campaigns API

  We're doubling down on APIs. Now you can create, schedule campaign emails from API. check [API documentation](/api-reference/introduction)

  ### Other improvements

  * Camapign Emails are now sent in batches instead of a burst of emails.
  * You can bulk upload large amounts of contacts without ui slowness.
  * Added delete domain API.
</Update>

<Update label="September 2024" description="v1.6.0">
  <Frame>
    <img src="https://usesend.com/hero-dark.webp" alt="Rebranded useSend hero" />
  </Frame>

  ### Suppression List

  Hard bounce and complained email addresses are automatically added to the suppression list. Works for both transactional and marketing emails.

  ### Rebranding to useSend

  From now on we [useSend](https://usesend.com). Make sure to update your docker image and sdks.
</Update>