Kit / Postmaster

Sending infrastructure for Kit, Inc.

This host names the mail servers that Kit, Inc. operates. If you administer a mail system and you have a question about mail from one of our addresses, this page tells you who we are and how to reach a person.

Contact a person

A person reads both mailboxes. We answer a delisting request or an abuse report from a mail operator within one business day.

Who operates these servers

Address ranges we send from

Kit, Inc. holds these ranges directly. The registry lists us as the operator, so the contact details above and the registry records agree.

Reverse DNS

Every sending address has a reverse DNS record under this domain, and each one resolves forward to the same address. A hostname takes this shape:

What this mail is

Kit is an email platform for independent creators. Our customers write newsletters and course material, and they send it to readers who asked for it. We send that mail on their behalf from the ranges above.

• A reader gives their address to a creator, on a form or a landing page.
• Every message carries a working unsubscribe link and a List-Unsubscribe header.
• An unsubscribe takes effect immediately, for that creator's list.
• We sign outbound mail with DKIM and publish SPF for our sending domains.
• We honour feedback loops, and a complaint removes the reader from the list.

Report a problem

Write to abuse@kit.com. Please include the full message headers, or the SMTP response your server returned. The headers carry an identifier that lets us find the exact message and the account that sent it.

We act on a report about unsolicited mail. We remove the reader, and we investigate the account that sent it.

Blocked one of our addresses?

Write to postmaster@kit.com with the address you blocked and the reason. We will tell you what the traffic was and what we changed. If you need us to reduce our connection rate to your servers, say so and we will.