Change User confirmation email behaviour

We had a service outage yesterday where we lost our ability to send e-mails. The issue is now resolved, and we’ve released some improvements to prevent this issue from happening again.

Yesterday’s e-mail outage was due to the fact the transactional e-mail sending service we’re using —Amazon SES— noticed a spike in our e-mail bounces and complaints, and decided to pause sending e-mails for our account.

The issue comes from the fact that we have a large amount of fake signups made by robots using real people’s e-mail addresses. When we send a confirmation e-mail, these people flag our e-mails as SPAM or report abuse, which can damage our e-mail sending reputation.

We now check with an external service if the e-mail provided is spammy. If the e-mail seems spammy we send an e-mail confirmation.

We also changed how the invitation system works and when accepting an invitation, e-mail confirmation isn’t necessary.