Letter Opener is a Ruby development utility that previews outgoing email in a web browser instead of sending it. It helps developers test layouts, content, and delivery behavior without configuring a real mail server or risking accidental messages. In Rails, it works as an Action Mailer delivery method and stores generated messages locally. Developers can customize the storage directory, browser-opening behavior, message template, and file URI scheme. The gem also supports non-Rails setups using Mail, Pony, or Action Mailer directly. Because it relies on a local browser through Launchy, remote servers, containers, and virtual machines may require adjusted settings or alternative mail-preview tools.

Features

  • Browser email previews
  • Safe local delivery
  • Rails Action Mailer integration
  • Custom storage location
  • Alternate message templates
  • Non-Rails support

Project Samples

Project Activity

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Categories

Email

License

MIT License

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Additional Project Details

Operating Systems

Linux, Windows

Programming Language

Ruby

Related Categories

Ruby Email Software

Registered

5 days ago