Keeping up with your customer’s expectations is more complex than ever before. And frankly, that’s not going to change anytime soon. With the rapid growth of new technologies, customer expectations inherently grow along. That isn’t surprising: the more products and services you have, the pickier you can – and probably should – be. As a business, you have to adjust to this rapid increase and preferably anticipate it. In our opinion, composable is the way forward.

The Composable Business

The term ‘Composable Business’ is not necessarily new. Starting in 2020, Gartner released a set of whitepapers and webinars about what they dubbed ‘composable business’ and how that’d help businesses to be more successful. In short, ‘composable business’ means creating a network of tools that communicate with each other but do not rely on each other to function correctly. The building blocks of a composable business are interchangeable, meaning that you can change specific parts of your business at any time.

Composability is based on three factors:

  1. Mindset;
  2. Architecture;
  3. Technology.

To build a composable business, you’ll need to get into that mindset. Everything you make or compose should be composability-first (we often use this term and API-first interchangeably). Anything is composable, including the way you manage your emails.

Composable Email Technologies

In the 2010s, most of us witnessed the rise of so-called all-in-one platforms. Often dubbed ‘monolithic’, these platforms are designed to be “composed all in one piece” you solve all your marketing challenges in this one platform! However, the term monolithic came closer to the Cambridge definition of the word: “too large, and unwilling or unable to be changed.”

With the rapid change in customer behaviour, this unableness to change turned into an issue. New, specialized tools took over quickly, solving customers’ unique problems and finding new ways to reach those customers. Moreover, in monolithic architecture, there is no way of replacing an unused or unliked part of the software, where you’d add an extra tool to solve that issue (and thus pay double).

Application Programming Interfaces

Those specialized tools brought a new (but also old) challenge: how do you manage customer data? Siloed is no option anymore; that was pretty much the point of these monolithic architectures. The solution: API (Application Programming Interface). This method creates the possibility of having different pieces of software communicate with each other – exchanging customer data, behavioural patterns, and more—all in real time.

With API-first email technologies, you’re composing an email network that is*:

  • Modular;
  • Agile;
  • Orchestrated;
  • Autonomous.

*Based on the Gartner Design Principles of Composability


Instead of purchasing an all-in-one platform, you’re designing a landscape of components for every team in your organization, including people involved in email. Your service desk needs to know whether an email has been delivered to your customer but doesn’t necessarily need to see if they’re part of the Christmas promotional campaign.

Your email marketer needs access to the transactional email design but shouldn’t worry about the Outlook SMTP relay server. Modularity gives people the proper access to the right tools.


When one of the tools in your landscape is not up to standards anymore, the composable architecture allows you to easily change your ‘old’ software to a more modern or scalable solution without rebuilding your whole architecture. Can your SMTP server not handle your volume anymore, or is your CDP too limited in functionality? Just get another one!

The composable mindset is about ‘change’ – as agile as humanly possible. Where traditionally, the change would be seen as scary or risky, the composable mindset views change as something you should embrace.


What data should be exchanged between what tools? Who should have access to what parts of the tools you’re using? A composable email landscape lets you choose how you want the components to communicate. Every business has tons of data about their customers, either 1st or 3rd party – the challenge is to make it accessible to those who should have access. One good example is Zusss, which connected its CDP to SendPro to add behavior-based recommendations to order confirmation emails.


The components in an architecture like this are designed to be working autonomously – to minimize the risk of a total blackout when one components errors or when one the architect decides to replace one component. The components do what they do best and can continue doing so whenever an error occurs somewhere else in the email sending process.

Composing an email architecture with SendPro

At Spotler, we’ve witnessed and taken part in shaping this trend for the future of email. Back when we started, the world was just turning its back to the monolithic architecture and started focusing on a more future-proof way of leveraging software. Over the years, the ‘best-of-breed’ solution that we offered as a transactional email provider turned more and more into the email infrastructure solution that we are today.

Our platform is designed and built from an API-first mindset. Whatever you want our platform to process, we can handle it, deliver the email, and turn data into statistics. This way, you can easily deliver and track your business emails.

Architecting email in a composable business

We’re firm believers in the composable future of businesses. And we do not just preach; we practice! Our marketing team is built with composability in mind. From lead generation to the after-sales process, we’ve built and are actively building on a composable architecture for our marketing and sales activities.