Client Libraries

To send email via, you will need to interact with our API. We offer a variety of official client libraries in various languages to make it easier. All of our client libraries are available at GitHub. In most cases the only configuration you will need to do is set your Domain Key.

Domain Keys

To send mail for your domain, you will need to supply a domain key. You can find your domain keys by visiting your domain at, selecting the settings cog from the main menu, then clicking ‘show’ next to ‘Domain Key’ on the right side of the page. You will see two domain keys, 'Live' and 'Test'. If you are only testing your application we recommend using the 'Test' key – as this key will not deliver emails (they will be available to view in your domain however).

Sending Emails

When sending an email, you need to pass along the template ‘slug’ so we know which template you’re trying to send. The slug is auto generated for you when you create a template (if you don’t specify one). If you’ve forgotten your template’s slug, or would like to change it – click the cog when viewing your list of templates.

Writing Your Own Client

If there is no official library for your language, or you cannot use our libraries for another reason, check out our guide for writing your own client library.

Migrating Existing Apps

Migrating an entire application at once is often not a feasible task. There are however several strategies for making the migration to easier. You can choose to move emails to only when they require updating, and you can also start by only using for new emails as they are added to your web app.

Using Your Own Delivery Provider

You can send email via your own email delivery provider if your plan allows you to (sometimes called ‘BYO Provider’).

To set up your own provider, you will need to select your provider from the dropdown on the settings page for your domain (click the cog in the main menu).

Email Provider Selection

Once your have selected your provider, you will be prompted for your credentials for that service and additional installation instructions will be displayed on the page.