MailerSend

MailerSend is an email delivery platform that provides REST APIs for sending, tracking, and managing transactional emails at scale. It offers programmatic access to sending domains, message and activity logs, email templates, recipients, webhooks, and delivery analytics. Nexla connects to the MailerSend API to ingest this data into your flows and to send emails and manage account resources as a destination.

Power end-to-end data operations for your MailerSend API with Nexla. Our bi-directional MailerSend connector is purpose-built for MailerSend, making it simple to ingest data, sync it across systems, and deliver it anywhere — all with no coding required. Nexla turns API-sourced data into ready-to-use, reusable data products and makes it easy to send data to MailerSend or any other destination. With comprehensive monitoring, lineage tracking, and access controls, Nexla keeps your MailerSend workflows fast, secure, and fully governed.

Features

Type: API

SourceDestination

• Seamless API Integration: Connect to any endpoint as source or destination without coding, with automatic data product creation
• Visual Composition & Chaining: Build complex integrations using visual templates, chain API calls, and compose workflows with data validation and filtering
• API Proxy: Expose curated slices of your data securely with a secure and customizable API proxy that validates and transforms data on the fly
• Request optimization with intelligent batching, retry, and caching to minimize API calls and costs

Prerequisites

Before creating a MailerSend credential, you need a MailerSend API token and the base URL for the MailerSend API. MailerSend uses bearer token authentication, with the token sent in the Authorization header of every request. API tokens are generated per sending domain and can be scoped with different permissions.

To obtain a MailerSend API token, follow these steps:

1. Sign in to your MailerSend account.

2. Navigate to the Integrations section, locate MailerSend API, and click Manage.

3. Click Create new token.

4. Enter a name for the token, then select the sending domain the token will be used for.

5. Optionally set an expiration date for the token. If no expiration date is set, the token expires 24 hours after creation by default.

6. Choose the token permissions. Full access grants access to GET, PUT, DELETE, and POST endpoints for all parts of your account, or you can select Custom access to restrict the token to specific areas.

7. Click Create token.

8. Copy or download the token immediately and store it securely. For security reasons, MailerSend displays the token only once.

The base URL for the MailerSend API is https://api.mailersend.com/v1. The API token is sent as a bearer token in the Authorization header for all requests. If your token is compromised, revoke it from the MailerSend dashboard and generate a new one. For detailed information about token management and available endpoints, see the MailerSend Developers Documentation.

Authenticate

Credentials required

Field	Required	Secret	Description
API Key	Yes	Yes	Your MailerSend API key for authentication.
Base URL	Yes	No	The base URL for the MailerSend API.

Create a credential in Nexla

1. After selecting the data source/destination type, click the Add Credential tile to open the Add New Credential overlay.

2. Enter a name for the credential in the Credential Name field and a short, meaningful description in the Credential Description field.

3. Enter your MailerSend API key in the API Key field. This is the API token you obtained in Prerequisites. The API key is sent as a bearer token in the Authorization header for all requests and must be kept confidential.

4. Enter the MailerSend API base URL in the Base URL field. This is typically https://api.mailersend.com/v1.

   If your API key is compromised, revoke it from the MailerSend dashboard and generate a new one. The API key grants access to your MailerSend account data according to the permissions it was created with and should be treated as sensitive information.

   For detailed information about API tokens, authentication, and available endpoints, see the MailerSend Developers Documentation.

5. Click the Save button at the bottom of the overlay. The newly added credential will now appear in a tile on the Authenticate screen during data source/destination creation.

Use as a data source

To create a new data flow, navigate to the Integrate section, and click the New Data Flow button. Select the MailerSend connector tile, then select the credential that will be used to connect to MailerSend, and click Next; or, create a new MailerSend credential for use in this flow.

Endpoint templates

Nexla provides pre-built templates that can be used to rapidly configure data sources to ingest data from common MailerSend endpoints. Select the endpoint from which this source will fetch data from the Endpoint pulldown menu. Available endpoint templates are listed in the expandable boxes below.

[Rest API] List Activity

Returns a paginated list of activity events for a given domain.

[Rest API] List Domains

Retrieve information about all sending domains associated with the account.

[Rest API] Get Domain

Retrieve detailed information for a single sending domain by its ID.

[Rest API] List Messages

Retrieve information about all messages sent from the account.

[Rest API] Get Message

Retrieve detailed information for a specific message by its ID.

[Rest API] List Templates

Retrieve all email templates associated with the account.

[Rest API] List Recipients

Retrieve a paginated list of email recipients associated with the account.

[Rest API] List Webhooks

Retrieve a list of webhooks configured for a specific domain.

[Rest API] Get Activity

Retrieve detailed information for a single activity event by its ID.

[Rest API] List Suppressions Blocklist

Retrieve a paginated list of email addresses on the account blocklist.

[Rest API] Get Analytics By Date

Retrieve email activity analytics data grouped by date for a given time range.

Once the selected endpoint template has been configured, click the Test button to the right of the endpoint selection menu to retrieve a sample of the data that will be fetched. Sample data will be displayed in the Endpoint Test Result panel on the right, allowing you to verify that the source is configured correctly before saving.

Manual configuration

MailerSend data sources can also be manually configured to ingest data from any valid MailerSend API endpoint, including endpoints not covered by the pre-built templates, chained API calls, or custom request parameters. Select the Advanced tab at the top of the configuration screen, and follow the instructions in Connect to Any API to configure the API method, endpoint URL, date/time and lookup macros, path to data, metadata, and request headers.

Once all of the relevant settings have been configured, click the Create button in the upper right corner of the screen to save and create the new MailerSend data source. Nexla will now begin ingesting data from the configured endpoint and will organize any data that it finds into one or more Nexsets.

Use as a destination

Click the + icon on the Nexset that will be sent to the MailerSend destination, and select the Send to Destination option from the menu. Select the MailerSend connector from the list of available destination connectors, then select the credential that will be used to connect to MailerSend, and click Next; or, create a new MailerSend credential for use in this flow.

Endpoint templates

Nexla provides pre-built templates that can be used to rapidly configure destinations to send data to common MailerSend endpoints. Select the endpoint to which data will be sent from the Endpoint pulldown menu. Then, click on the template in the list below to expand it, and follow the instructions to configure additional endpoint settings.

[Rest API] Send Email

Send a single transactional email via the MailerSend sending API.

[Rest API] Send Bulk Emails

Send multiple transactional emails in a single bulk request.

[Rest API] Add Domain

Add a new sending domain to the MailerSend account.

[Rest API] Update Domain Settings

Update settings for an existing sending domain.

[Rest API] Delete Domain

Delete a sending domain from the MailerSend account.

[Rest API] Delete Template

Delete an email template from the MailerSend account.

[Rest API] Create Webhook

Create a new webhook to receive event notifications from MailerSend.

[Rest API] Update Webhook

Update an existing webhook configuration.

[Rest API] Delete Webhook

Delete a webhook from the MailerSend account.

Manual configuration

MailerSend destinations can also be manually configured to send data to any valid MailerSend API endpoint. Select the Advanced tab at the top of the configuration screen, and follow the instructions in Connect to Any API to configure the API method, data format, endpoint URL, request headers, attribute exclusions, record batching, and response webhooks.

Save & activate

Once all endpoint settings have been configured, click the Done button in the upper right corner of the screen to save and create the destination. To send the data to the configured MailerSend endpoint, open the destination resource menu, and select Activate.

The Nexset data will not be sent to the MailerSend endpoint until the destination is activated. Destinations can be activated immediately or at a later time, providing full control over data movement.