Gumroad

API and webhooks

Gumroad has a public API at gumroad.com/api, and an official command-line tool for it. Use it to pull sales into a report, or to check a licence key from your own app. Check the API page for the events and fields that are available before you design around them.

No-code automation

Zapier lists a Gumroad app. A simple flow: when a sale comes in, add the buyer to your email list in Kit or Mailchimp, and post the sale in Slack.