Deliverability
Inbox placement, IP reputation, authentication, and why cold email lives or dies on infrastructure details.
Deliverability
DKIM, SPF, DMARC, DANE Explained — And Why You Need All Four
The four email authentication standards, what each one actually does, how they compose, and why DANE is the one most cold-email providers quietly skip. A deliverability engineer's walkthrough.
Deliverability
The Real Cost of Shared Mailboxes (With Calculator)
Per-mailbox pricing destroys outbound margins at scale. Here is the math on Google Workspace vs Microsoft 365 vs dedicated VPS for a 50-mailbox cold email operation — and why flat-rate infrastructure wins past ~20 mailboxes.
Deliverability
Why Your IP Reputation Matters More Than Your Copy
Deliverability is 80% infrastructure and 20% content. Beautiful copy on a bad IP does not reach the inbox. Here is what actually drives placement, in the order it matters.