Microservices vs. APIs: What’s the Difference?

Charles Heal

Sales and Business Development Director

Updated: August 15, 2022
6 min read

If a digital transformation is on the horizon for your ecommerce business, you may be wondering about microservices and APIs, and how to tell them apart. These two concepts are at the heart of modern web applications, and they overlap in many use cases.

First, it’s essential to understand how microservices and APIs are different, how they’re used, and how they can work together to benefit your ecommerce business.

In this article, we will discuss how to leverage microservices and APIs to your advantage, and as a byproduct, you’ll impress your developer friends with your profound knowledge. A win-win in our book.

What’s a Microservice?

A microservice refers to a single service within a microservice architecture. In turn, microservice architecture is a method of building a web application by dividing its functionality into modular components, or “microservices.”

Imagine a collection of loosely coupled services, almost like building blocks, that operate independently from each other. With microservices (also known as composable architecture), you’re free to easily add, swap, and remove parts of your architecture. Each microservice carries out a single task, but the scope and number of microservices depend on your unique business needs.

In this model, your commerce platform is a piece of the puzzle, not the central engine. This means that your commerce engine won’t get bogged down with the weight of your entire ecosystem.

The History of Microservices

Before microservice architecture came around, platform-based architecture dominated the ecommerce world. Platform-based might still rule the school if not for the rapidly changing needs of modern ecommerce vendors.

Traditional platform-based applications involve a single platform at the center of your solution that handles all features and functionality.

However, if an ecommerce platform becomes overstuffed with functionality, processes, and programs, it also turns into your single point of failure. Like an iMac computer, you’ll eventually need to re-platform the entire thing if you require a newer version or different features.

Like a custom-built PC, microservice architecture provides endless flexibility to enhance every part of your system and work on a more granular level of your architecture. You can also select the best-of-breed tools and functionality to ensure you’re providing your customers with memorable experiences.

The Benefits of Microservice Architecture

Flexibility: Your teams can build a specific microservice in the best way without worrying about impacting other elements in your system.
Stability: If a microservice experiences an issue or breaks down, your other services remain safe.
Security: If a microservice becomes compromised, it won’t affect other components.
Efficiency: Instead of relying or waiting on other teams to deliver projects, each team can focus on an individual microservice that’s not connected to anything else.
Focused knowledge: Instead of understanding your entire system architecture, your developers only need to master specific areas.
Easy updates: Enjoy the simplicity of updating one microservice at a time instead of taking on your entire system. Save money, time, and effort by frequently launching minor, less significant updates.

By dividing and conquering responsibilities, microservices make the software development process faster, easier, and more efficient.
However, a group of decoupled microservices needs something to bring them all together in a meaningful way. That’s where APIs come in.

What’s an API?

An Application Programming Interface, or an API, is a part of a web application that interacts with other applications. A software’s API establishes how two applications share and exchange data.

Modern applications vary in data and functionality, and APIs act as a medium for effective and standardized communication.

An API is located between a software’s core components and the outside, making it an interface for developers. Programmers can access specific parts of an application’s back end without understanding how everything works in the app.

REST APIs

Because APIs are the frameworks through which programmers can communicate with applications, they take many shapes and forms.

Representational State Transfer, or REST, is a framework for developing APIs. The appropriately dubbed REST APIs are most prevalent in cross-platform integrations and are used in microservices.

How do REST APIs Work?

REST defines the framework for developing APIs that make them secure and efficient. REST APIs work by receiving HTTP requests and returning responses typically in JSON (JavaScript Object Notation) format.

Developers can quickly learn to build or communicate with a REST API because HTTP (Hypertext Transfer Protocol) is the standardized protocol for web-based data transfer. API design styles further include GraphQL, SOAP, gRPC, etc.

What’s the Difference Between Open APIs, web APIs, and Internal APIs?

There’s one more distinction to be made when it comes to APIs:

Open APIs: Publicly available APIs that give developers, even third-party developers, programmatic access to a particular application or service.
Web APIs: A web API arranges communication between web servers.
Internal APIs: These APIs are limited to use within an application, with restricted access even within an organization.

What are the Benefits of an API?

Because APIs allow for software integrations, they are an inseparable part of modern software. APIs allow individual software to share information and work together.

In ecommerce, you’ll find APIs hard at work everywhere, from logging in to your account to paying for your purchases. For example, Helly Hansen may offer a payment option via PayPal. Because PayPal and Helly Hansen are separate companies, an API manages the communication between the two entities.

First, Helly Hansen uses PayPal’s payment gateway API to request your payment information. Then, PayPal’s API accepts the request, verifies it, retrieves the data, and sends it to Helly Hansen. Lastly, Helly Hansen uses your payment information to complete the purchase.

Because of APIs, this communication between applications is efficient and easy. Neither Helly Hansen nor PayPal needs to access each other’s databases, and you never have to leave the original website.

What’s the Difference Between Microservices vs. APIs?

Within microservice architecture, microservices use APIs to interact with each other. A microservice module uses a private, internal API to communicate with another module in the system.

Each microservice has an API that defines the requests it may accept and how it responds. These APIs generally adhere to the REST principles.

Because each microservice is different, they use APIs in unique ways. A single microservice may require several APIs, or one API may provide access to several microservices.

APIs also play a role without microservices. Web APIs help facilitate communication between web applications, and internal APIs can be used without microservices.

Microservices Architecture: Future-Proof Your Ecommerce Solution

Microservices architecture is viewed as the next stepping stone in ecommerce, but it’s not for everyone. A microservices migration, through a phased replacement or a complete replacement, is a major overhaul and can require significant business maturity and effort.

However, there are small steps you can take to open the door to a microservices approach. For example, did you know going headless is just one possibility in phasing in a migration to a microservices architecture? Even swapping out just one specific feature for a microservice is a start! Read our blog post for detailed information on how to carry out a microservices migration.

Because microservices and APIs work together simply, quickly, and efficiently, it opens the door for scalability, customization, and efficiency within your teams. It’s a simple concept that’s open to everyone—and major players on the market are already hopping on the bandwagon.

Trust the Experts

At Vaimo, we are familiar with navigating new terrain with ecommerce companies. We’ve helped hundreds of brands and retailers assess the best solution for their unique needs and goals.

We work closely with vendors in the MACH Alliance, a non-profit industry body that advocates for open and best-of-breed enterprise technology ecosystems. We strive to maintain a group of the best partners, functionality, and tools to offer the best building blocks when choosing microservices architecture.

Trust the experts—our work speaks for itself. Talk to us today about your ecommerce solution!