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Deliverability for developers: Insights from Sinch product leader Josh Odom

What does email deliverability have to do with developers, and what are the areas of disruption as we look forward into emerging tech like AI? If you thought deliverability was just marketing’s responsibility, you’re dead wrong.



Email deliverability isn’t just a task for marketing, and the product, protocols, and features that impact it constantly change. So, what is key for developers? What aspects of deliverability are within their control?

The first thing to know is that deliverability is hinged on performance. From how optimized your sending infrastructure is to how well your messages are coded, there are many pieces separate from the authentications and best practices that marketers pursue.

But before we dive in, let’s start with the basics. What is deliverability?

Understanding the importance of deliverability

In short, deliverability is email jargon for getting your message into the inbox.

Beyond that, though, deliverability centers around increasing engagement and email ROI. Now, we know that ROI may not be a primary concern for all devs, but deliverability is more than just a wallet issue, deliverability is a product of performance. And we’re not talking marketing metrics like bounce rates, we’re talking infrastructure efficiency, file sizes, caching mechanisms, cross-platform compatibility, and responsive designs.

Deliverability isn’t just about if your email makes it to the inbox, it’s about the condition in which it arrives.

Here's an example from the email dev perspective: The majority of email clients don’t support many things that can be done with HTML. So, in addition to marketing’s best practices for deliverability you have to be pragmatic with how you develop your emails. This means testing your messages outside of your local environment with an email preview tool to ensure compatibility across different operating systems and devices.

Coding with HTML and keeping deliverability in mind can be a challenge. Learn how to deliver HTML emails with Mailgun-go.

How deliverability and dev are connected

Your deliverability is first impacted by a tough decision: Should you have your own on-premises email servers and mail transfer agents you maintain yourself , or should you outsource to a cloud-based solution?

The on-premises/cloud-based debate is one for the ages, but if you’ve chosen the cloud-based route, welcome – you’re in the company of most modern senders.

The tools you choose to implement within your email program will further impact your performance from this on-prem/cloud decision. When it comes to email, development goes way beyond the coding language used to design the actual emails. Infrastructure engineers are the ones actually optimizing performance at scale, and their role is critical to strong email deliverability.

Here are a few things to consider:

Choose the right tech stack

Your tech stack is your tools. For email deliverability, that means tools that perform email verification, inbox placement testing, previewing, reputation monitoring, delivery rate monitoring, and monitoring capabilities like blocklist monitoring, spam check, and IP/domain health.

Evaluate the pros and cons of different technologies

Synergy is something to value when looking into how to compile your toolset. There are a lot of sender agnostic tools out there – meaning you can partner with one platform for verification and another for IP monitoring. But there are also holistic platforms with built-in integrations for a suite of products.

Consider scalability and future growth

Select a platform or construct your on-premises infrastructure, with growth in mind. One advantage to cloud-based solutions is many have a scale up mindset to meet changing sending needs.

Incorporate automation

Regardless of your toolset, automation should be at the forefront of your strategy. This can apply to your sending strategy like with transactional emails that are triggered by customer action (think password resets, shipping confirmations, etc.)

You should also consider automations that segment mailing lists based on user interaction, a key component to keep email deliverability under control.

How developers enhance deliverability

We’ve covered some of the high-level points of how developers and engineers can impact deliverability. Now, we’re going to give you a playbook for increasing deliverability by improving just one element: speed.

Optimizing load times and performance

Speed is everything. Swift load times are critical for messages, given that the average attention span of a user is about three seconds. That’s less time than the five second food on the floor rule.

While this statistic pertains specifically to website page load speed, you can bet that the inbox is no different – it’s just a bit harder to track when users click out of a message. And that’s the blind spot with email: Engagement metrics can tell you a lot, but not everything.

Here are two things email developers can do to improve load times and test you’re their code and performance before sending an email.

  1. Minimize file sizes, optimize images, and implement responsive design principles.

  2. Ensure cross-platform compatibility with inbox preview testing

Need a guide to creating responsive and optimized emails that render across all clients and devices? We’ve got you covered. Check out these 12 tips for email rendering to learn more.

Future trends and emerging tech

The algorithms are complex and ever evolving. And with email, you don’t know what you don’t know. Without X-ray vision to peer into the inner workings of mailbox providers, the filters, protocols, and standards of getting into various inboxes remains cloaked in a degree of mystery.

But that doesn’t mean your email program is defenseless. In fact, the best defense is to be ready to adapt. That’s why paying attention to the optimization of your performance and your HTML practices is so crucial.

And that’s not the only area where adaptation is needed. Communication is constantly morphing, and businesses need to keep up with the trends to stay relevant – not just in email, but in omnichannel experiences in general.

We know in the future technologies like AI and chatbots will continue to play a significant role in enhancing user experiences and engagement – yet another reason to be really intentional when choosing platforms and tools, and deciding how to construct your infrastructure.

Wrapping up

Email isn’t stagnant, and it's crucial to stay up to date with the latest trends and technologies. So, make sure you seek out opportunities to expand your knowledge and skills, whether it's through courses, experience, or helpful content *wink*.

If deliverability isn’t already a consideration in how you set up your infrastructure or code your emails, hopefully this post has convinced you that it’s at least something to think about.

To keep up with the more technical side of emailing, be sure to subscribe to our newsletter for interviews, insights, and inside scoops from our own developers.

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