Ask HN: Mails form JavaScript (client) securely?

I want to send mails to me whenever sth happens on my site without implementing server.

I'd love to use mailgun or mandrill, but this expose my API key. Is there a service where I can still use API, but make it safe by sending mails only to myself?

Thanks, I've seen that - but it's not a solution.

"Keep in mind that your API key is visible to anyone, so any malicious user may use your key to send out emails that can eat up your quota."