New major features in Halon Engage 16

• Delivery Guru Warmup: Real time IP warmup with mailbox provider specific logic
• OpenMetrics support: Custom metric exports for observability tools
• Bounce Normalizer: Groups similar bounces and strips message level noise
• Azure Linux support: New build option for Microsoft’s cloud OS

We’re releasing Halon Engage 16 with a major update to Delivery Guru. The new feature brings smart improvisation to one of the most critical and error-prone parts of email delivery: warming up new IP addresses.

This change supports a bigger shift in how email operations are run. It helps teams move from manual work to more proactive, controlled, and composable systems. That’s the goal behind Dynamic Email Operations. And it’s why we’re building Delivery Guru to cover more of the pipeline, one step at a time.

What happens during warmup?

Mailbox providers treat new IPs with caution. They don’t know the sender, so they watch for signs of spam. If too much email arrives too quickly, they block it, delay it, or place it in the spam folder. That can harm the sender's reputation early, and recovery is slow.

Warmup is meant to solve this. Start slow. Send a small volume. If the response is clean, increase gradually. But if something looks off, slow down or stop. That’s the idea.

In practice, though, most warmups are based on fixed plans. Teams use static schedules. They don’t respond to live signals. They don’t customize behavior for different mailbox providers. And when things go wrong, the team is left guessing or reacting.

Delivery Guru Warmup fixes this

With Halon Engage 16, warmup becomes part of Delivery Guru. It automates the process from day one. It adapts based on real-time data. It handles complexity without extra load on the team.

Here’s what it does:

• Smart volume ramp-up: Delivery Guru builds a daily volume plan based on previous delivery and engagement. It avoids large jumps. It monitors performance before scaling.
  
  

• Real-time reputation tracking: If bounce rates rise or delivery times get longer, the system reacts. It can pause sending, reduce volume, or shift focus to stronger-performing domains.
  
  

• Mailbox-provider-specific warmup rules: Not all mailbox providers behave the same way. Gmail tolerates higher volumes if engagement is strong. Microsoft tends to greylist new IPs early. Yahoo may trigger temporary blocks. Delivery Guru adapts to each of these automatically.
  
  

• Simple control, no spreadsheets: The warmup plan is visible in the Delivery Insights. You can see the current status, next steps, and historical behavior. There’s no need to track progress manually.
  
  

Warmup fits into a larger shift

Warmup isn’t just a setup task. It affects how quickly you can launch, how reliably you deliver, and how often teams end up firefighting avoidable problems. Delivery Guru Warmup aligns to three of the six principles of Dynamic Email Operations:

• Automate, do not repeat: You no longer need spreadsheets, daily volume checks, or manual mailbox provider specific  tweaks. The system handles those decisions, based on live signals.
  
  

• Gain true visibility: You can track each IP’s status, volume plan, and mailbox provider specific behavior in one place. No need to pull logs or check separate tools.
  
  

• Scale effortlessly: Warm one IP or fifty. It doesn’t add more effort. The system handles each plan independently, without added setup or supervision.

What else is new in Halon Engage 16?

2. Bounce normalizer: We’ve added a new bounce normalizer that makes bounce data easier to read, group, and act on. It removes message-level noise like hashes, IPs, and personal details, so similar failures get grouped together. This helps with reporting and rule creation.

3. Azure linux support: You can now run Halon Engage on Azure Linux. This expands deployment options and simplifies builds for teams already using Microsoft’s cloud.

4. Dynamic policy ordering: Delivery policies now follow a strict evaluation order. This allows plugins like warm-up and backoff to override static policies with more control.

5. Prioritized DNS resolution: Domains that matter most to your business can be moved to the front of the DNS resolution queue.

6. Web UI improvements: The UI now supports autoscaling through shared session storage, displays active DNS resolver activity, and runs long running actions like message deletion in the background. This keeps the interface responsive and makes it easier to scale across clusters, especially useful for larger teams and high volume environments.

These are just a few highlights. There are many more smaller improvements throughout this release to improve performance, increase flexibility, and make day to day operations with Halon Engage smoother.

What’s next?

This release is part of a larger roadmap. Delivery Guru will continue to grow. It will handle more parts of delivery, more signals, and more decisions. Over time, it will help teams replace routine tasks with responsive systems that run smarter by default.

But the shift doesn't stop there. Halon Engage is evolving across the board. Each improvement reduces friction and gives teams more control without added effort.

You’ll still be in control. But you won’t need to watch every bounce, adjust every plan, or explain every delay. Halon Engage will take care of the low level decisions so your team can focus on strategy, scale, and performance.

Halon Engage 16 is now available.

If you’re an existing customer, reach out to your account manager to activate warmup and explore what’s new.

If you’re evaluating Halon and want to see features like warmup in action, schedule a demo with our team.