Resend
An email API for developers that sends transactional email, like receipts and password resets, from your own domain.
Your code calls Resend's API, and the email goes out from an address on your own domain. Receipts, password resets, the boring emails that really do have to arrive.
The step people skip is DNS. You add a few records that prove you own the domain. Miss one, or typo it, and your mail lands in spam or nowhere. That's the answer to most "my emails aren't sending" questions.
On Base44 you get a choice. Built-in SendEmail is fine for low-volume mail to your own users. Reach for Resend when you want richer templates or more volume from your own domain. You can connect it through Base44's Resend integration (Builder plan and up) or call it from a backend function with the key in secrets.
I've got Resend running in production on client apps, next to Stripe.
Related:Integration, Backend function and Secrets.
Where I've used it: