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Infrastructure

The biggest mistake in cold outbound is sending from your main domain. One bad week of sends, one spam complaint spike, and your hello@yourcompany.com lands in the junk folder for the next six months. We’ve seen it happen.

We don’t let that happen.


We buy lookalike domains for you. These are close variations of your real domain:

Your domainExample lookalike
acmecorp.comgetacmecorp.com
acmecorp.comacmecorpteam.com
acmecorp.comtriacmecorp.com

We buy 3–5 of these. They’re cheap (~$12/year each) and completely separate from your production infrastructure. If one domain gets flagged or blacklisted, we rotate off it and the others stay clean.

Your main domain is never touched.


We provision 10 Google Workspace mailboxes across the lookalike domains, typically 2–3 mailboxes per domain.

Each mailbox sends a maximum of 30–40 emails per day. This keeps each individual inbox within safe limits while the combined volume across 10 inboxes reaches 300–400 sends per day (~5,000/month).

We use natural-sounding names to maximize deliverability:

james.harris@getacmecorp.com
sarah.chen@triacmecorp.com
m.johnson@acmecorpteam.com

Not:

outreach1@getacmecorp.com
info@triacmecorp.com

Every domain gets full authentication configured before a single email is sent:

SPF — Declares which mail servers are authorized to send on behalf of the domain. Without this, receiving servers have no reason to trust your emails.

DKIM — A cryptographic signature attached to every email. Proves the message wasn’t altered in transit and that the sender controls the domain.

DMARC — A policy that tells receiving servers what to do when SPF or DKIM fails. Starts at p=none for monitoring, then hardens to p=quarantine after warmup.

We verify all three are correct using MxToolbox before the first send. This takes 2–3 days after domain purchase due to DNS propagation.


New mailboxes need to build a positive sender reputation before cold outreach begins. Without warming, your emails land in spam from day one.

We warm all 10 mailboxes simultaneously using an automated warmup network (real inbox-to-inbox exchanges that generate opens, replies, and moved-from-spam signals).

PeriodDaily sends per mailboxWarmup activity
Days 1–70 cold emailsWarmup network only (~20 exchanges/day)
Days 8–145–10Light cold volume starts
Days 15–2115–25Ramping up
Days 22–3030–40Full capacity

The warmup network runs continuously in the background even after warmup completes, maintaining reputation between campaigns.


It’s rare with our setup, but it happens. Our response:

  1. Immediately pause sending from that domain
  2. Identify the cause (usually a spam complaint spike from bad list quality)
  3. Rotate active sequences to clean domains within 24 hours
  4. Decide whether to delist the domain or retire it and buy a new one

We monitor blacklist status daily using automated checks against the major RBLs (Spamhaus, Barracuda, etc.).


All domains and mailboxes belong to you. If you leave BuyerBrains:

  • Domains are transferred to your registrar account
  • Google Workspace seats are transferred to your billing
  • We hand over all credentials

Nothing is locked to our platform.

Want us to run this for you?

BuyerBrains handles the full system end-to-end — signals, copy, sends, and booking. Book a 15-min intro to see if we're a fit.

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