The tools in this category
Full deliverability infrastructure — domains, inboxes, warmup, monitoring.
Modern deliverability infrastructure competitor to Maildoso.
Smartlead's built-in infrastructure offering.
Dedicated inbox warmup tool.
Alternative dedicated warmup tool.
Our take on deliverability infrastructure
Deliverability infrastructure is the layer most cold email teams don't think about until deliverability collapses. Your cold email tool doesn't send email — it uses inboxes and domains you provide. If those aren't set up correctly, no cold email tool in the world will save you.
The five tools below cover domain purchase, DNS setup (SPF, DKIM, DMARC), inbox creation, and warmup — the operational layer that makes cold email actually work at scale.
Maildoso is our default for teams scaling past 5 sending domains. Mailforge is the modern alternative. Smartlead's built-in infrastructure works if you're already on Smartlead. Mailreach and Warmup Inbox are dedicated warmup tools.
How we'd stack these tools together
Deliverability infrastructure sits underneath your cold email tool. Buy domains, warm inboxes, monitor reputation — then send from Smartlead or Instantly. Without this layer, cold email at any scale collapses.