I'm not sure I've ever told this story before, but back in 2019, when I was working on our very first Zapier integration, I committed a blunder that haunts me to this day. I had swapped over my local development environment to point to my production API key for my own personal newsletter on Buttondown, just to make sure some of the subscriber actions were working. Having done that, I ran a couple test actions to create new emails without remembering to swap back to a sandbox account. The rest, as they say, is history. By the time I realized what I had done, I had unintentionally spammed my lovely subscribers a dozen or so times with a smorgasbord of UUIDs.
This feature, in many ways, is for my former self and for anyone who has executed a curl command and immediately regretted what they see. You can now turn on test mode in Buttondown, which retains all functionality except that every single outbound email goes to the email address associated with the account. This makes it easy to safely iterate on integrations without ever worrying that you're going to blast someone or perhaps a hundred someone's. Head on over to the documentation for test mode to learn more!