The Mailtrap Ruby SDK has been significantly expanded. It now covers the full Mailtrap feature set - from batch sending and sandbox testing to contact management, templates, and more.

Here's what's new:

Batch Sending — Send up to 500 emails in a single API call using a shared base configuration. Useful for newsletters, notifications, and any high-volume use case.

Sandbox Mode — Send emails directly to your Mailtrap Sandbox inbox for testing, without touching real recipients. Just initialize the client with sandbox: true and your inbox_id.

Multiple Client Support — You can now run transactional and bulk delivery methods simultaneously within the same Rails app, making it easy to separate email streams by type.

Expanded API Coverage — The SDK now includes modules for:

• Sending Domains API

• Email Sandbox management (Projects, Inboxes, Messages, Attachments)

• Contact management (CRUD & listing)

• Accounts API

Support of reply_to — The from_content mail builder now supports a reply_to field.

Full documentation and code examples are available in the Ruby SDK guide and the GitHub repository.