Deliverability

Reaching the inbox is a shared responsibility. Authentication and infrastructure are ours; list quality and content are yours, and no provider can fix those for you.

What we handle

• DKIM signing, and a custom MAIL FROM so SPF aligns with your From domain.
• Managed sending IPs with warm-up, and reputation monitoring per tenant.
• Automatic retry of transient failures with exponential backoff.
• Suppression of hard bounces and complaints, scoped to your organization alone.
• Feedback loops with the major mailbox providers.

What you handle

Publish DMARC

DKIM and SPF prove your mail is authentic. DMARC tells receivers what to do when something fails, and increasingly it is expected rather than optional. Start in monitoring mode:

_dmarc.yourdomain.com. IN TXT "v=DMARC1; p=none; rua=mailto:dmarc@yourdomain.com"

Read the aggregate reports for a few weeks, confirm nothing legitimate is failing, then move to p=quarantine and eventually p=reject. Going straight to reject is how companies discover a forgotten invoicing system that was sending as their domain.

Send both HTML and plain text

An HTML-only message scores worse with filters, and some clients render nothing else. Write the text version properly rather than stripping tags out of the HTML.

Use a recognisable sender

{ "email": "receipts@yourdomain.com", "name": "Acme Receipts" } beats a bare address. Avoid noreply@ where a reply would be reasonable — recipients who cannot reply mark mail as spam instead.

Make unsubscribing trivial

For anything recurring, include one-click unsubscribe headers. A spam complaint costs you far more than an unsubscribe does.

{
  "headers": {
    "List-Unsubscribe": "<https://yourdomain.com/u/abc123>",
    "List-Unsubscribe-Post": "List-Unsubscribe=One-Click"
  }
}

Keep your list clean

• Validate addresses at the point of capture, not at send time.
• Use double opt-in for anything recurring.
• Stop mailing addresses that have not engaged in a year.
• Never buy a list. It will hard-bounce heavily and land you in spam traps, and both are effectively unrecoverable.

Numbers that matter

• Delivery rate — above 95%. Below that, look for invalid addresses and check your DNS.
• Hard bounce rate — under 2%. Above 5% and sending is paused automatically.
• Complaint rate — under 0.1%. That is one in a thousand; it is a tighter bound than it sounds.

Track these from your event stream, and alert on them. By the time you notice a reputation problem in your open rates, it has been building for weeks.

On tracking

Open and click tracking are off by default. Both require rewriting your links and embedding a pixel, which measurably hurts deliverability and breaks URLs that automated recipients need to parse. If you enable them, use a custom tracking domain so links carry your name rather than a shared one.