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Link: Fastmail creates aliases for mailing list recipients to protect their privacy

I subscribed to Fastmail’s newsletter and was surprised to see they use Mailchimp to send them. But it turns out they create temporary email aliases for each subscriber every time they send an email.

Each time we send a newsletter, we create new temporary aliases for everyone to ensure we respect any changes in your newsletter preferences and keep your personal addresses private from our external email marketing tool (Mailchimp).

The temporary address will then expire, meaning you’ll disappear without a trace on Mailchimp and never receive any mail sent to that alias again.

At the moment, newsletters are sent 2–10 times per year. Each time a new newsletter is sent, a new list of aliases will be imported, reflecting any new additions or subtractions to users on the list.

It’s impressive – and cool – to see privacy-conscious companies walking the walk.

Cooler still, they don’t even store generated aliases:

It’s actually not too much effort! We generate time-limited aliases by hashing together your real address + expiration time + some randomness. When we get the mail, we reverse that process to look up your account and deliver it.

(We don’t even store the generated aliases!)