Domain rotation
Sending high-volume cold outreach across multiple domains so no single domain crosses reputation thresholds.
Sending 5,000 emails/day from one domain looks suspicious to mailbox providers — even legitimate volume gets throttled. The standard mitigation is to spread sends across multiple domains (e.g., yourcompany.com, yourcompany.io, yourcompany.co), each carrying a fraction of the volume.
Naive rotation (manual, in the UI) is fragile — easy to accidentally send all traffic from one domain. BoomSauce enforces rotation at the send-queue layer: each outbound message picks the next eligible mailbox by health score, not by user input.
Rule of thumb: budget one domain per 50–100 daily sends, one mailbox per 30–50 daily sends. Beyond that you're asking for reputation damage.