Microservices Vs API

When discussing software architecture and integrations, you’ve probably heard two fancy-sounding terms: APIs and microservices.

Some people also have confusion about whether Microservices and APIs are simple concepts or not. Well, it is a severe and debatable concept, which must be discussed with in-depth research.

This blog will guide you through all Microservices and APIs’ differences, their reliance on each other, and much more.

What Is API:


An API, short for Application Programming Interface, is a software-to-software interface. APIs provide a secure and standardized way for applications to work together and deliver the information or functionality requested without user intervention.

Technically speaking, APIs are usually implemented and stored between the software core components and the application front-end interface.

To provide your software the ability to perform a particular task or borrow that functionality from a third-party service provider, developers need to build APIs or integrate third-party APIs with their software solution. In the case of integrating a third-party API, developers need to refer to the high-level API reference document, best practices, or guidelines provided by the owners.

Types Of  API:

Technical Core Engineers declare majorly two types of APIs, Which are as follows:

  1. Internal APIs are used only for internal application use cases, such as in-app communication, and are restricted to authorized development and business management team members.
  1. External APIs are the ones with which third-party APIs and resources are integrated to share public company data with associated third parties. e.g., SaaS applications, public cloud services, etc.

Popular API Design Style:

  • REST APIs stands for Representational State Transfer APIs, which are built from the REST framework with the aim of cross-platform integration. These APIs can also be used in microservices. The REST APIs work on HTTP requests and represent findings in JSON format.
  • SOAP APIs stands for Simple Object Access Protocol APIs, which allow processes using OS, like Linux and Windows, to communicate using HTTP and XML formats. By integrating your application with this API – your solution can create, update, drop (delete), and recover records, like profiles, login credentials, etc.
  • GraphQL APIs get you faster and more stable predictable results in an organized manner on your raised queries as they have access to all application data source points, even when your device’s internet connection is slow.

What Is The Role Of An API:

All of this flexibility requires microservices to talk to each other. APIs offer this capability, as long as they are carefully implemented, used, and managed.

An API offers a standardized means for a system to access applications, services (and microservices), or data outside of the code’s direct environment. One microservice can use an API to access the functionality of another microservice.

Unfortunately, not all APIs are standardized or follow the same format. There is general acceptance and use of some protocols and application code — such as representational state transfer, simple object access protocol, JavaScript object notation, and extensible markup language. Still, a developer can build these “standardized” environments with pretty much anything, which complicates communication between apps and services.

What Is Microservices:

Microservices, or microservice architecture, is an approach to application development in which a large application is built from modular components or services. Each module supports a specific task or business goal and uses a simple, well-defined interface, such as an application programming interface (API), to communicate with other sets of services.

What Is Microservices

Microservices are defined in two contexts:

  • Microservice is a loosely-coupled software development architecture helping to develop a large and complex software solution by creating and integrating multiple small development components together.
  • And a small, tiny development component can also be represented as a Microservice.

In simple words, Microservices are a collection of small development components, when gathered together – create an extensive, flexible software product

How Microservices Work:

In a microservices architecture, an application is divided into services. Each service runs a unique process and usually manages its own database. A service can generate alerts, log data, support user interfaces (UIs), handle user identification or authentication, and perform various other tasks.

The microservices paradigm provides development teams with a more decentralized approach to building software. Each service can be isolated, rebuilt, redeployed, and managed independently. For example, if a program isn’t properly generating reports, IT staff can trace the problem to a specific service and then test, restart, patch and redeploy that service as needed, independent of other services.

Benefits Of Microservices Architecture:

  • can be developed and deployed using different languages and tools;
  • require less development time;
  • can scale quickly;
  • can be reused in different projects;
  • contain better fault isolation;
  • are faster and far less resource-intensive to deploy and load balance;
  • can be deployed in relatively small teams; and
  • work well with Containers.

Characteristics Of Microservices Architecture And Design:

Microservices architecture consists of discrete components and services; their intercommunication and data exchanges create the functions of a complete application. Typical characteristics of a microservices design and architecture include the following:

Unique: Design and deploy services to accomplish a specific function or address a specific requirement.

Decentralized: Ideally, services have few if any dependencies, although loose coupling requires frequent and extensive communication.

Resilient: Design services for maximum fault tolerance. A single service failure shouldn’t disable an entire application.

Use APIs: A microservices architecture relies heavily on APIs and API gateways to facilitate communication.

Data separation: Ideally, each service accesses its own database or storage volume.

Difference between Microservices V/s APIs:

The Difference Between Microservices and API. An API is a contract that provides guidance for a consumer to use the underlying services. 

By this point, you’re somewhat familiar with the concepts of both APIs and microservices. Now, let’s highlight the differences:

ScopeAn architectural application development approach from integrating many interconnected services for each functional requirement.A protocol or standard to integrate applications and make them easily. Communicate with each other.
PurposeBuild loosely-coupled servicesEnable effective communication between two applications or application components
WorkingUse APIs for enabling servicesMake services open-source to allow third-party users to connect their application with
CharacteristicsLoosely coupled, scalable, Faster, manageable, and decentralizedLightweight, Fast, and extensively specified
GoalProviding distinct service components to an applicationoffers a user-friendly, easy-to-access interface to do more.
Use CasesA competitive successor to monolithic architecture for creating a decentralized applicationImplement and integrate specific functions into an application

The Impact Of APIs On Microservices:

The API is an application communication tool that enables communication between two services. Reality check, though APIs are an effective service package, they need to be integrated with other services or microservices in order to become useful, which could be:

  • Function as a Service
  • Machine Learning as a Service
  • Software as a Service

You could also say that APIs are the brain of microservices, which makes them connected and distributes microservices with users. Moreover, APIs help microservices to step out of their sort of monolithic architecture and gain decentralized characteristics for what they are created.

Also Read: Best Technologies To Build Microservices Architecture

How Do Microservices Work With APIs:

Microservices is an approach to building an application that breaks its functionality into modular components. APIs are part of an application that communicates with other applications. So, APIs can be used to enable microservices.

 Employ Composable Enterprise Approach

The composable enterprise architecture was introduced by Gartner to work with this emerging IT trend, which is built upon Packaged Business Capabilities to enable:

  • Infrastructure as an application (IaaS)
  • Infrastructure automation (IaC)
  • Multi-cloud Governance & Orchestration
  • Portfolio rationalization
 Microservice Security

In Microservices architecture, security should be the top priority, especially in the case of Service Mesh. To effectively secure a Service Mesh, you need to use protective APIs and an API Gateway – for the service encapsulation.


Deeply understand your application microservices architecture and the working of microservices, which will help you find the components and loopholes to harden your microservices-based application and boost its performance. This microservices-based application optimization best practice will help you provide a value solution to your application user base.