Hey folks! We've made some behind-the-scenes improvements to how we handle problematic subscribers that should make your life a bit easier.

A brief history lesson

When Buttondown first launched, we used a single flag, is_spammy, to mark subscribers who were problematic—whether their email was missing, malformed, or looked like it came from a bot. Over time, we added more specific types, like "malformed," to better describe these cases. Eventually, this led to a long list of subscriber types that all meant, in practice, "we can't deliver to this address."

However, this approach had two main issues. First, the term "spammy" suggested intentional bad behavior, which often was not true. Second, the actions you could take on these subscribers were basically the same, regardless of the specific type. So, having lots of categories just added confusion without real benefit.

To simplify things, we've now consolidated several of these types—like "malformed" and "spammy"—into a single "undeliverable" status. All subscribers we can't deliver to are now grouped together, but with a specific reason attached (e.g., malformed address, flagged by our systems, etc.). This makes it easier to see why someone can't receive emails, filter your list, and automate actions.

There are still a few other "bad" subscriber types: "complained," "disposable," and "blocked." But for most cases, you'll just see "undeliverable" with a clear reason.

In short: instead of juggling multiple confusing categories, you now have a single, clearer "undeliverable" status for subscribers we can't reach, making management and automation much simpler.

What do you need to do?

Nothing! This change happened automatically. If you had any subscribers marked as "spammy," they're now marked as "undeliverable" with the appropriate reason. Your existing filters and segments will continue to work as expected.

This is part of our ongoing effort to make subscriber management more intuitive while giving you the detailed information you need to maintain a healthy list.