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September 11, 2025
Improvement: all endpoints now return a success and message field in the error response bodies.error and path top-level keys are now deprecated but will continue to be supported for some time for backwards compatibility.
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August 21, 2025
The docs have been updated to reflect that the email parameter is optional in the Update contact endpoint if a userId is provided.
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May 23, 2025
Improvement: data variables are now optional in the Send transactional email endpoint. Read more
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April 29, 2025
New: a new Idempotency-Key header when sending events.
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March 28, 2025
New: a new Idempotency-Key header when sending transactional emails.
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February 28, 2025
New: a new endpoint for listing transactional emails and their data variables.
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January 14, 2025
New: new endpoints for creating contact properties and listing contact properties.Depcrecation: the List custom fields endpoint is now deprecated in favor of the new List contact properties endpoint.
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December 18, 2024
New: we added description to mailing list objects in the List mailing lists endpoint.
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November 5, 2024
Improvement: the maximum payload size for the transactional endpoint has been increased from 1MB to 4MB, allowing for more or larger attachments.
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September 6, 2024
New: our new Nuxt module is now out!
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August 16, 2024
New: our new Ruby SDK is available!
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August 15, 2024
New: we added an isPublic attribute to mailing list objects in the List mailing lists endpoint.
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June 28, 2024
New: there’s a new addToAudience parameter in the Send transactional email endpoint can add contacts to your audience.
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June 18, 2024
New: support for our new mailing lists feature.You can now add contacts to and remove contacts from mailing lists in the Create contact, Update contact and Send event endpoints.There is also a new endpoint for retrieving your mailing lists.
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April 18, 2024
New: you can now Find contacts by userId.
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April 9, 2024
New: a new endpoint for testing your integration and/or API key: API key.
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March 21, 2024
New: you can now include event properties in requests to the Send event endpoint.
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March 13, 2024
Improvement: we removed behavior that returned a 400 Bad Request response if an unrecognized property was added to Contact endpoints.
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February 9, 2024
Improvement: sending in a payload that contains an unrecognized property will now return a 400 Bad Request response.
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January 25, 2024
Clarification in the API docs that userId can be used in a Send event request.
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November 6, 2023
New: we added a new endpoint for querying custom contact properties.
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October 30, 2023
Our official JavaScript/TypeScript SDK is now available!
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October 12, 2023
New: we now accept dates as a custom contact property type. View the available formats.