SPF, DKIM and DMARC Explained Without the Migraine

<blockquote> <p><strong>TL;DR</strong><br /> SPF (Sender Policy Framework) is the first line of defense against email spoofing, allowing domain owners to declare which IP

<h1> From p=none to Enforcement: A Working Sequence for DMARC Rollout </h1> <p>DMARC adoption is easy to start and hard to finish. Publishing a policy record takes minutes. Moving

<p><em>By the team at <a href="https://mailtester.ninja" rel="noopener noreferrer">MailTester Ninja</a> — a real-time email verification API that stores nothing.</em></p> <p>We

<p>DMARC has been an Informational RFC since 2015. That changed this month.</p> <p><a href="https://www.rfc-editor.org/rfc/rfc9989.html" rel="noopener noreferrer">RFC 9989</a>

<a href="https://news.ycombinator.com/item?id=49035563">Comments</a>

<p>Short answer: put each user reminder on a queue, make the consumer idempotent, retry transient delivery failures with backoff, and move exhausted work to a dead-letter queue