All glossary entries
Glossary
Email warmup
The process of gradually ramping a new mailbox's sending volume to build sender reputation before production.
New domains and mailboxes have no reputation at Gmail, Outlook, or Yahoo. Send 1,000 cold emails on day one and you'll land in the spam folder for months — sometimes permanently.
Warmup solves this by sending a small, ramping volume of emails to "friendly" mailboxes that open, reply, archive, and mark-not-spam in human-realistic patterns. The mailbox provider sees this engagement and gradually elevates the sender's reputation.
BoomSauce runs warmup on the CheddarInbox P2P network — a private pool of real mailboxes owned by other tenants. Real engagement signals, not synthetic traffic. 21-day default ramp; configurable per-mailbox.
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