To enable a mailing list, add this to your _config.yml:

mailing_list:
  enabled: true
  text: "Subscribe to my amazing list!"
  button: "Click it!"
  endpoint: "/manage/subscriptions"

At the very least you need to set enabled to true, the others are option (and default to “Subscribe to mailing list” and “Join” and “/subscribe”)

Email is validated using a simple set of rules: it must have an @ symbol, and characters before and after it, and at least one dot in the end section.

When a user enters their email and hits the button a POST request is made to your server at the endpoint. You can either implement something to handle this endpoint, or just grep through your logs for email addresses made to POST /subscribe/{emailAddress}.