Trap rails from sending mail via SMTP

Nov 16, 2007

Trap rails from sending mail via SMTP Matt Mower has released a handy little tool called Mailtrap. Basically what it does as act as a very simple SMTP server that accepts requests from ActionMailer, but writes them to file instead of emailing them on.

Installation is very straight forward:

sudo gem install -y mailtrap

And then start it up:

mailtrap start

Which will start the mailtrap app to listen on port 2525. Now all that is left to do is change the config in your rails app to connect to localhost:2525 in either /config/environment.rb or /config/environment/development.rb:

ActionMailer::Base.perform_deliveries = true
ActionMailer::Base.raise_delivery_errors = true
ActionMailer::Base.delivery_method = :smtp
ActionMailer::Base.smtp_settings = {
  :domain => "",
  :address => "localhost",
  :port => 2525,
Hi, I'm Glenn! 👋 I'm currently Director of Product @ HashiCorp, and we're hiring! If you'd like to come and work with me and help make Terraform Cloud even more amazing we have multiple positions opening in Product ManagementDesign, and Engineering & Engineering Management across a range of levels (i.e., junior through to senior). Please send in an application ASAP so we can get in touch.