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Field notes on cold email.
Written by people who run cold email every day. Deliverability, infrastructure, sequences and the operations behind them.
Cold email infrastructure: the complete setup checklist (and what to automate)The cold email infrastructure checklist: domains, redirects, inboxes, SPF/DKIM/DMARC, tracking, warm-up, rotation, monitoring, and which steps to automate.Read the guide →
How to recover a burned cold email domainTo recover a burned cold email domain, stop sending, check blocklists and Postmaster Tools, fix the root cause and ramp slowly, or retire the domain.
Running cold email for 20 clients without losing trackTo run cold email for 20 clients, give each a workspace, name domains and inboxes consistently, keep an infrastructure ledger and report weekly.
What cold email really costs: domains, inboxes, warm-up and toolsCold email at 150,000 emails a month means about 214 inboxes and 72 domains. Here is a transparent cost model for inboxes, domains, tools and your time.
Why cold email lands in Outlook junk (and how to fix it)Cold email lands in Outlook junk because of failed authentication, bulk-style signals and tenant filters. Fix DMARC alignment, links, volume and test placement.
Email warm-up for cold email: what it does, and why yours isn't workingEmail warm-up builds sending history for new inboxes, but it can't fix bad lists, broken auth or spammy copy. Here's a ramp schedule and what to check first.
Gmail, Yahoo and Microsoft bulk sender rules: what cold emailers must do in 2026Gmail, Yahoo and Microsoft require bulk senders to use SPF, DKIM, aligned DMARC, one-click unsubscribe and keep spam under 0.3%. What cold email must do.
How many domains and inboxes do you need for cold email?To size cold email infrastructure, divide monthly volume by sending days and a 30–50 per-inbox daily cap, add a buffer, then use 2–3 inboxes per domain.
How to set up SPF, DKIM and DMARC for cold emailSet up SPF, DKIM and DMARC for cold email with one SPF record under 10 lookups, 2048-bit DKIM, and DMARC at p=none with reports before quarantine.
The 3-step cold email sequence we'd send tomorrowA 3-step cold email sequence template: a short intro with one ask, a value-adding follow-up in the same thread, and a polite last touch, plus timing and subject lines.Get early access. Join the waitlist.We're opening Zylar in waves. One email when your spot opens.