When people think of software architecture, they often picture layers of code. But in recent years, there’s been a shift from this model—known as the monolithic approach—toward a more modular development style. This new approach, known as microservices, has given rise to a phenomenon known as API sprawl.

This blog post will explain what API sprawl is, the factors causing its growth, its consequences, how to identify it, and the benefits of having a well-managed policy.

This blog post originally appeared on the Traceable blog.

Original Post

What is API Sprawl?

Each system component is broken down into its own independent service in a microservices architecture. These services communicate with each other via application programming interfaces (APIs). The move away from monolithic programming means that instead of one giant codebase, there are now many small codebases—each with its own set of APIs. Every team is responsible for its service.

API sprawl is many APIs of many different types, spread over many locations and managed by many other teams.

This sprawl leads to zombie APIs: those that are no longer used but are still lurking around, taking up space. It also leads to inconsistency in design and functionality, as different teams develop their APIs according to their preferences.

Factors Driving API Sprawl

Microservices

The first factor driving API sprawl is the rise of microservices architecture. There are many benefits to using microservices over monolithic technology, so just returning to monoliths is not a good answer to the problem. Unfortunately, microservices teams tend to get siloed off from each other. When siloed, they are less likely to share best practices or collaborate on API design. A breakdown in communication and sharing leads to each team developing their APIs, which adds to the overall sprawl.

The Cloud

The second factor driving API sprawl is the rise of the cloud. The cloud makes it easy to provision new servers and services on demand. Unfortunately, many servers hosting many APIs can lead to a situation where there are many unused or underused APIs, which adds to the clutter.

DevOps

The third factor driving API sprawl is the rise of DevOps and continuous delivery/integration. In this model, software is released frequently, in small increments. These small increments can produce instability in the APIs, and some developers may find it easier to develop their own stable API instead of dealing with constant breaks. Furthermore, it introduces yet another team to the development and deployment process. The more teams, the more difficult it is to manage communication between them.

Complexity

The fourth factor driving API sprawl is the size and complexity of businesses and their software systems. Gone are the days when an enterprise could have a single software system doing one thing. In addition, companies are composed of many different teams, each with its services, goals, and business priorities.

Speed

The fifth factor driving API sprawl is the need for speed. In today’s fast-paced business world, companies face pressure to release new features quickly. The pressure can lead to development teams focused on getting something done instead of doing it right. In the case of API sprawl, developers are not searching for an API that already exists or is further in development.

This need for speed leads to:

  • Lack of governance: When there is no central authority governing the development of APIs, it leads to a Wild West situation where everyone does their own thing.
  • Lack of documentation: If there is no clear documentation for how developers should use an API, then different teams will develop different conventions and standards. This lack of standardization leads to inconsistency and confusion.
  • Lack of tooling: Without the proper tooling, it can be challenging to keep track of all the different APIs and their dependencies. Not having a clear picture makes it hard to make changes or update APIs without breaking things.

Consequences of API Sprawl

API sprawl can lead to significant problems, including security vulnerabilities, decreased productivity, and increased complexity.

Security Vulnerabilities

With so many different APIs, it becomes more challenging to keep track of who has access to which API and what they can do with it. The lack of awareness of access and authority can lead to an increased risk of data breaches and other security issues.

Decreased Productivity

Decreased productivity is one of the most common consequences of API sprawl. With too many APIs, it can be difficult for developers to find the right one. Without the ability to quickly find appropriate APIs, it leads to wasted time spent searching and, eventually, developer frustration. In addition, when too many APIs exist, it’s more likely that some will be duplicates of others.

Increased Complexity

Increased complexity is another common consequence of API sprawl. When there are too many APIs, it can be challenging to keep track of them all. The lack of clarity on what is available and its location can lead to confusion and errors. Furthermore, when multiple teams are working on different services, coordinating between them cannot be easy. Lack of coordination can lead to delays in releases and increased costs.

Decreased Agility

With so many different APIs to keep track of, it can be challenging to make changes quickly. The inability to react rapidly to the changing business landscape can lead to missed opportunities and a competitive disadvantage. It also becomes more challenging to make changes and update systems. This is the most significant issue with monolithic applications, and microservices with API sprawl lead to the same issue, so now you’ve rebuilt a system with the same problems. The inability to change can lead to frustration and stagnation.

Increased Costs

More APIs mean more development and maintenance costs. It can also lead to wasted efforts as teams duplicate work already done by other teams.

Decreased Trust

When users see many different APIs and no practical or logical way to manage or search them, they may not trust that the system is well-designed or well-maintained. The lack of trust can lead to them using other systems or building their own, thus contributing further to the problem.

How to Identify API Sprawl

Identifying API sprawl is straightforward but not trivial. Consider the following:

  • Do all of your APIs perform a unique job, calculation, or service?
  • Do you have clear and consistent documentation for all of your APIs?
  • Do you have effective tooling in place to manage all of your APIs?
  • Are there clear governance procedures for new API development and deployment?
  • Can developers easily find the correct API to use in their development?
  • Do security audits find no vulnerabilities in your APIs?

If you answered no to any of these questions, you either have a problem with API sprawl or are at risk of developing it in the future.

Benefits of a Well-Managed API Ecosystem without API Sprawl

The benefits of a well-managed API ecosystem include

  • reduced risk of data breaches, hacks, and slowdowns
  • ability to deliver new and improved functionality to the business faster
  • reduced cost of providing business functionality
  • improved developer satisfaction and morale
  • increased trust in the system by users and developers

Wrapping Up

API sprawl is a real problem, but with tools like Traceable AI, you can manage your organization’s APIs and prevent sprawl from happening in the first place. In addition, it can help organizations with existing API sprawl to get it and keep it under control.