> For the complete documentation index, see [llms.txt](https://docs.mailtrap.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.mailtrap.io/guides/integrations/sinatra.md).

# Sinatra

This guide shows you how to integrate Mailtrap with Sinatra and send emails using the Email API.

Before we start, you'll need to:

* [Verify your sending domain](/email-api-smtp/setup/sending-domain.md)
* [Create and save an API key](/email-api-smtp/setup/api-tokens.md)

## Send emails using Sinatra and Mailtrap

To integrate Mailtrap and send emails via Sinatra, copy the following script into your configuration:

{% code title="app.rb" %}

```ruby
require "sinatra"
require "mailtrap"

set :port, 5000
set :bind, "0.0.0.0"

get "/" do
  content_type :json

  mail = Mailtrap::Mail.from_content(
    from: { name: 'Mailtrap Test', email: 'YOUR-EMAIL-HERE' },
    to: [{ email: 'RECIPIENT-EMAIL-HERE' }],
    subject: 'Hello World',
    html: '<strong>it works!</strong>',
  )

  client = Mailtrap::Client.new(api_key: 'YOUR-MAILTRAP-API-KEY-HERE')
  response = client.send(mail)

  response.to_hash.to_json
end
```

{% endcode %}

Once you copy the script, make sure to:

* Insert your Mailtrap API token in the `api_key:` field
* Enter your email address in the `from:` field
* Enter your recipient's email address in the `to:` field

{% hint style="info" %}
To learn more about API integration, see [Mailtrap Email Sending API Integration](/email-api-smtp/setup/api-integration.md).
{% endhint %}


---

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