In the past, I've sent email from Heroku apps using the Gmail server, like this:
config.action_mailer.deconfig.action_mailer.delivery_method = :smtp
config.action_mailer.smtp_settings = {
:address => "smtp.gmail.com",
:port => 587,
:domain => 'derp'
:user_name => 'derp.bot',
:password => 'derp42069',
:authentication => 'plain',
:enable_starttls_auto => true }
Since then I've enabled two-factor authentication for most of my domains. Before I do the same for my latest domain, will in wreck havoc with Rails code like you see above?
If the change does break your code, you could fix work around it by using an application-specific password.