PostShiba now supports IP pools. Group dedicated sending IPs into named pools and choose a pool for each message.
For example, give a high-volume customer their own pool while the rest of your platform keeps sending on shared IPs. Keep transactional and marketing mail on separate clusters and pools.
Route with one header
After attaching a pool to your cluster, select it with a message header:
This works over SMTP, HTTP inject, and the REST API. Messages without the header keep using the cluster's own IPs.
Set traffic weights
Assign relative weights to distribute mail across the pool's IPs.
Warm up with overflow
When every IP in a pool is warming, enable overflow to send excess mail through the cluster's shared IPs. You still control the volume ramp.
Team Administrators can create a pool from Network → New pool in the dashboard. The setup guide covers configuration, warm-up, and delivery checks.