MailCatcher

Spec sheet

Purpose

MailCatcher runs an SMTP server that catches messages and displays them in a web interface.Read 10 Oct 2026 · mailcatcher.me

API

Its REST-style endpoints provide message lists and metadata in JSON, message content, attachments, and full source.Read 10 Oct 2026 · mailcatcher.me

Integrations

The site gives setup instructions for Rails, PHP, and Django applications.Read 10 Oct 2026 · mailcatcher.me

Support

The maker asks users to file an issue and include the complete message when reporting processing problems.Read 10 Oct 2026 · mailcatcher.me

License

The project is released under the MIT License.Read 10 Oct 2026 · mailcatcher.me

Attachments

It lists attachments and allows individual parts to be downloaded.Read 10 Oct 2026 · mailcatcher.me

HTML preview

It rewrites HTML to display embedded images and opens links in a new window.Read 10 Oct 2026 · mailcatcher.me

Images and links

It rewrites HTML to display embedded images and open links in a new window.Read 4 Oct 2026 · mailcatcher.me

Installation

The site instructs users to install MailCatcher with `gem install mailcatcher` and run it locally.Read 10 Oct 2026 · mailcatcher.me

Intended use

The setup instructions direct applications to send mail to a local SMTP endpoint for inspection in development.Read 4 Oct 2026 · mailcatcher.me

Limitation

MailCatcher does not completely support UTF-8 sent directly over the wire and advises using a mail library that encodes according to SMTP server capabilities.Read 10 Oct 2026 · mailcatcher.me

Limits

The maker says mail processing is basic and that UTF-8 is not completely supported directly over the wire.Read 4 Oct 2026 · mailcatcher.me

Live updates

Messages appear instantly in browsers supporting WebSockets; otherwise, the interface updates every thirty seconds.Read 10 Oct 2026 · mailcatcher.me

Message views

It shows HTML, plain text, and source versions of messages when available.Read 10 Oct 2026 · mailcatcher.me

Requirements

The repository README says MailCatcher requires Ruby 3.3 or newer and notes build tools may be needed for dependencies.Read 4 Oct 2026 · github.com

Where Specifiction places it

• Email Testing Software#21 of 287.2