Configure a hosted Plunk domain and secret key

These guides cover hosted Plunk. The project also offers self-hosting instructions; provisioning those servers is not required to connect an application to the hosted service.

Prepare the hosted sending identity

1. Add and verify the application domain using the current domain guide.
2. Select the correct project/account and create a secret API key for server-side operations.
3. Keep the sk_ secret key out of frontend code. The documented pk_ public key is restricted to the tracking endpoint, not a public send capability.
4. Record the current hosted API base and schema from the API overview, rather than copying an older deployment’s endpoint.

Use the supplied DNS instructions and leave employee mailbox routing unchanged unless enabling a separate approved receiving feature.

Verify the right key and environment

Run one controlled transactional send and inspect the hosted project’s activity. A public tracking key successfully accepting an event does not prove it can send mail or administer contacts.

Distinguish custom product-event tracking, system email events, and direct transactional sending. Accidentally triggering a marketing workflow from a test can create real external messages.

MailKite credentials are a separate connection. Moving a workflow requires intentional domain, template, event, and suppression mapping—not simply replacing a Plunk secret with a MailKite key.