How do I automate subscribing with Carrd & Substack?

As it turns out, Carrd.co works with many newsletter platforms, but not Substack.com due to its current lack of an API.

Carrd supports just about every other newsletter platform there is so I don't believe they'd let this slide if they had a way to make it happen.

So to work around this limitation, I started out 'manual' with a simple custom form. When a subscriber clicked the Subscribe button on my landing page, it would trigger an email to me with their email address. I would then subscribe each person on my Substack site manually. That worked for a couple of weeks, but then I noticed the number of subscribers was growing and most were coming in while I was sleeping.

This meant my new subscribers weren't getting the critical Welcome email until I got around to manually subscribing them. I even noticed I missed a few - for several days. This sucked and was demoralizing.

That's when I tried to leverage the POST URL (/api/v1/free?nojs=true) that Substack's very own subscribe form used. It failed but exposed the critical nugget of info I was missing. And, more importantly, it was something I had not found on the all-powerful Google.

If you send a GET request to https://your-account.substack.com/[email protected], it will attempt to auto-submit the subscription form immediately after the page finishes loading.

That was the secret sauce I was missing. And I can proudly report that it is working well after being in place for a couple of weeks now.