Kestrel

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Verify it works

Email’s real failure modes — DKIM alignment, inbox rendering, the bounce webhook round-trip, one-click unsubscribe in a real client — only appear once deployed (docs/SPEC.md §10). Run this checklist on staging first (sending only to addresses you own), then again on production before the first real send.

1. Test send to yourself

In the editor (/dashboard/), open a draft and use Send test email to deliver the rendered post to an address you control. A test goes through the same render path as a real send (I5), so a clean test is a real guarantee, not a lookalike.

  • The test arrives in the inbox.
  • It renders correctly (images load, layout holds, links work).
  • The subject and preheader read as intended.

2. DKIM alignment

Open the received test’s raw source (Gmail: Show original) and read the Authentication-Results header.

  • spf=pass, dkim=pass, and dmarc=pass, all aligned to send.example.com.

If any fail, revisit Sending-domain DNS — alignment is the single best predictor of landing in the inbox.

3. One-click unsubscribe in a real client

Every message carries a one-click List-Unsubscribe header (RFC 8058) and an in-body unsubscribe link. Both point at the app’s token-scoped endpoint — no login, no confirmation step (docs/SPEC.md §7).

  • The mail client shows its built-in Unsubscribe affordance.
  • Clicking it (or the in-body link) records the unsubscribe immediately.
  • The address shows as unsubscribed in the editor’s Subscribers view and is excluded from the next send (I2).

4. Bounce / complaint webhook round-trip

Prove the provider’s events reach the app and suppress the address on their own. Use the provider’s built-in simulator addresses (they never mail a real person):

  • SES: send to bounce@simulator.amazonses.com (hard bounce) and complaint@simulator.amazonses.com (complaint).
  • Resend: use its documented test addresses for bounce and complaint.

Then check:

  • The event arrives at the webhook (/webhooks/ses or /webhooks/resend) and passes signature verification. For SES, confirm the SNS subscription shows Confirmed (the app completes the handshake automatically) and the Worker logs show the event applied.
  • The simulated address appears suppressed in the editor, whatever its consent state, and is excluded from every subsequent send (I1).

5. Send-now review window

  • Scheduling (or Send now) creates a visible, cancelable Send before any mail leaves, and canceling it stops the send (I6). Nothing fires the instant it is requested.

When every box is checked on production, the instance is ready for a real send to your confirmed subscribers.

These steps are operator-run and cannot be performed from inside the app or from a development session — they need your live Cloudflare account, real DNS, a provider out of the sandbox, and real inboxes. Treat them as the acceptance test you run by hand.