I'm building a small tool called FormBeep[1] that sends a notification to your phone when someone submits a form on your website.
It started as a client problem, then something which I also experienced so decided to built it. It's just one small script and work seamlessly across platforms.
Curious, were you already aware of ntfy.sh (which has webhooks) when you built it?
Shit! I was not aware!
So FormBeep is designed to work with WhatsApp since most people prefer whatsapp notifications!