e-Commerce Mobile Commerce

Noah Strerath 7 Minutes

API vs. Middleware: Which Approach is Better for Your Business?

How many software applications are in use daily at your company? Our experience has shown that online retailers, in particular, have an extremely diverse system landscape. They often connect their online shops with ERPs (such as Microsoft Dynamics), which manage the majority of their business processes. In turn, the ERP is connected to shipping service providers, payment providers, and many other applications. Is your software pool structured similarly?

Very good, because deep integration allows numerous processes to be automated and accelerated. If you have landed on this post, there is a good chance that you are looking to build a system architecture like this. If so, you should definitely keep reading.

There are essentially two ways to build an integration using ERP: with middleware or through an API (Application Programming Interface). In this post, we want to show you why the latter is the better solution in most cases.

What are the differences between API and Middleware?

Both API and Middleware serve to link two systems that are separate from each other. While Middleware is an additional software that mediates between both systems, data transmission takes place directly with the help of an API. The API approach offers a number of advantages due to its more compact structure.

What does API vs. Middleware actually mean?

You've probably encountered the abbreviation API before. But what exactly does it entail? And what does the term Middleware mean? In the following, we want to provide you with a closer look at the basics.

Communication via API

The API can be understood as a direct connection between two systems. It acts as a kind of messenger that transfers information from one system to the other and plays back its response in reverse. Many tools, such as applications for email marketing (e.g., Mailchimp), e-commerce platforms (e.g., Shopify), payment providers (e.g., Klarna), etc., provide developers with their own APIs. With these, the systems can be integrated into an existing software landscape.

Over the years, ESYON has developed its own solutions that allow you to harmonize various systems. We'll show you which ones below in the article.

Communication via Middleware

Unlike integration using APIs, there is no native connection between two systems communicating through Middleware. Instead, Middleware forms an additional software layer that mediates between the systems.

Illustration explaining an API. Shows the flow of data from a database through a web server to the API, then to the Internet and on to a web application and program. Text: 'What is an API?'

5 Reasons Why API Integration is the Better Solution for You

You might already suspect it: Due to the architecture, the two alternatives, API or Middleware, result in a solution that is clearly superior in most cases. Seamless integration via API is preferable to Middleware whenever possible. But why? Here are 5 reasons in favor of the API.

Compact System Structure

When you introduce additional software between two systems, the complexity of your software pool automatically increases. To keep business operations simple and process chains as short as possible, you should avoid unnecessary intermediate solutions.

Lower Maintenance Effort

Every software requires updates from time to time, resulting in a certain amount of maintenance and organization effort. By avoiding the use of middleware, you can reduce the maintenance burden of your system landscape. Additionally, you eliminate a potential security risk if the middleware is no longer supported or regularly updated.

Real-time Data Synchronization

Seamless integration enables real-time data transmission, automating numerous standard processes like invoicing and payment booking. Although automation can also be achieved with middleware, the data transfer rates are slower.

More Efficient Processes

Automation brings a fundamental advantage: it eliminates manual work, minimizing error sources and making your processes more efficient. This lays the foundation for the scalability of your company

Higher Flexibility

Compared to middleware, API integration usually offers higher flexibility. Since it is embedded at a deeper level in the systems, adjustments and changes can be made quickly and easily to respond to changing business requirements. In contrast, configuring middleware is often significantly more complex.

Integrate Your E-Commerce Business with Microsoft's ERP Solution and Reap Numerous Benefits


  • Familiar Office Environment: Microsoft Dynamics closely aligns with the interface of Microsoft Office, greatly simplifying your team's daily work with the ERP.
  • Omnichannel Capability:: Seamless integration allows for centralization of all your sales channels in a single solution.
  • Consistent Data Foundation: Product, customer, and order information, inventory levels, and more are synchronized in real-time across all channels, ensuring consistency.
  • Short Time-to-Market:: Depending on the scope, an e-commerce platform based on Microsoft Dynamics can be deployed within weeks.
  • Configurable Products: Using our Product Configurator, you can offer customers in your online shop the ability to customize their desired product from various components. This promotes a personalized shopping experience and enhances customer satisfaction.
  • High-Performance SaaS Solution: Upon request, you can operate your e-commerce platform in the Microsoft Azure cloud, making it even more performant, scalable, and resilient.

ESYON, Your Specialist in E-Commerce System Integration

With over a decade of experience in e-commerce, we have developed a range of integrations to harmonize various systems. The foundation of our integration is the ERP Microsoft Dynamics 365.

D365X Connector

With the D365X Connector, you can connect OXID eShop with Microsoft Dynamics. Enjoy all the benefits of seamless integration, as described above, and manage your online shop directly in your Microsoft ERP.

[Learn More]

Shopify Plus Connector

The Shopify Plus Connector serves as the counterpart to the D365X Connector for the Canadian e-commerce platform, which is gaining popularity. Shopify Plus is ideal for online retailers looking to quickly establish an e-commerce platform. Our connector makes this process particularly easy and convenient.

[Learn More]

Amazon Marketplace Connector

Considering its reputation and reach alone, Amazon's online marketplace is enticing. With the Amazon Marketplace Connector, you can bring your Amazon business and Microsoft Dynamics together, automating numerous processes that manual handling could quickly bottleneck your marketplace presence. Additionally, you gain more control and transparency in the Amazon realm, filled with regulations and fees.

[Learn More]


The integration of systems into existing e-commerce businesses is a critical step for efficient business operations and scalable company development. With APIs, a direct, seamless connection between different software solutions offers numerous advantages in terms of system structure, maintenance effort, real-time data synchronization, process efficiency, and flexibility. ESYON's specialized connectors, based on Microsoft Dynamics 365, illustrate how the benefits of API integration can be utilized to create a comprehensive and harmonized e-commerce ecosystem. Migration to API-based integrations represents the current trend and is the preferred method for modern and future-proof e-commerce strategies.

Reading Tip: By integrating your Amazon Order Management, you save valuable time and avoid unnecessary errors. Learn more in this article.

Frequently asked questions about API vs. Middleware:

Whenever possible, the integration of one system into another should utilize an API, as the more compact system structure offers numerous advantages. We have explained these benefits in the article.

The use of middleware is worthwhile whenever native integration between two systems is not possible, meaning they are not compatible. However, this scenario is becoming increasingly rare today, making direct integration through APIs the more common method.

Middleware should only be considered when direct API integration is not possible due to incompatibility between the systems that need to be connected.

When using middleware, risks such as increased system complexity, higher maintenance effort, and potential security risks due to lack of updates may arise.

API integrations generally enable more efficient scalability for businesses by reducing manual effort and promoting higher process efficiency.

ESYON specializes in integrations with Microsoft Dynamics 365 but also develops connectors for other popular e-commerce platforms such as OXID eShop, Shopify Plus, and the Amazon Marketplace to enable centralized control and synchronization of sales channels.