Is a Loosely Coupled Architecture Right for Your Dev Process?

Cloud-native architectures and applications enable development teams to ship code faster, cut costs, and deliver apps that are more scalable, secure, and reliable than ever before. It’s how modern businesses are turning software into a powerful competitive advantage. But this is possible only when your developers have the right tools and skills to build, deploy, and manage applications in a cloud-native world.

In our first blog post on this topic, we looked at how cloud-native is transforming the developer experience. One of the most important changes we've seen is a shift toward building cloud-native applications that leverage a loosely coupled architecture. In today's blog post, we'll discuss what we mean by a "loosely coupled" application architecture. We'll also look at the pros and cons of a loosely coupled approach and how to decide whether it's the right approach for your needs.

Table of contents:

• What Is a Loosely Coupled Architecture?
• The Evolution of Loosely Coupled Architecture
• Loosely Coupled Architecture Pros and Cons
• One Size Does Not Fit All: Tips for Assessing a Loosely Coupled Approach
• An Approach to Consider for Achieving DevOps Excellence

What Is a Loosely Coupled Architecture?

We use the term "loosely coupled" to describe a software architecture that minimizes the number of dependencies between a system's components. Instead, it takes a more flexible, modular approach, breaking the system into independent components that can be developed, scaled, and maintained without breaking the application as a whole.

One of the most important benefits of a loosely coupled approach is that it gives dev teams a more flexible and agile work environment. Each team can build, deploy, scale, and even fail independently — moving fast and staying laser-focused on delivering high-quality, high-value code.

Research from the DevOps Research and Assessment (DORA) and other organizations shows that when teams excel at working within a loosely coupled architecture, they're more likely to achieve successful continuous delivery — a key milestone for elite cloud-native performance.

The Evolution of Loosely Coupled Architecture

Today's approach to working with a loosely coupled architecture involves two closely related concepts that have evolved over the past few decades: one focusing on back-end development and the other adapting the same approach to front-end development.

The evolution of a loosely coupled architecture started back around 2004, as developers started splitting backend services into microservices.

A microservices architecture divides an application portfolio into a collection of small, self-contained, single-function services with well-defined interfaces and operations that communicate with each other and can be evolved independently. Today, it's not unusual for enterprise app portfolios to run using hundreds of microservices, many of which are deployed repeatedly within an application environment. Netflix, for example, runs more than 1000 microservices.

Then, perhaps a decade ago, the concept of a loosely coupled architecture evolved to include a related concept: micro-frontends. As the name suggests, it aims to bring the same principles used in microservices to the realm of frontend development.

In a micro-frontend environment, different teams build different parts of the UIs that connect to different microservices. For example, in a digital banking portal, a bank may provide a number of customer offerings, such as online accounts, credit card, loans, and investment. Each of these business offerings could be evolved independently by different teams that work in isolation.

Micro-frontends give front-end development teams the freedom they need to address those differences quickly and effectively — keeping teams focused and productive, and giving the bank an important competitive differentiator.

Loosely Coupled Architecture Pros and Cons

Teams that work with a loosely coupled architecture gain some important advantages:

• Teams stay agile and maintain independent CI/CD pipelines. Services and user experiences can evolve independently, in whatever way makes the most sense for a given scenario. This helps teams stay focused, deploy code more frequently, and achieve shorter lead times.
• Developers can take a "divide and conquer" approach to creating business value. A loosely coupled architecture allows teams to specialize in one area of the business or even a single technology problem, which can reduce complexity and allow for a simpler code QA process.
• Services can scale independently at a reasonable cost. With the separation between services, development teams can scale application capabilities with greater precision, ensuring that businesses pay only for what they actually need.
• Dev teams can work in technology-agnostic environments. A loosely coupled architecture keeps developers in control when it comes to choosing the right framework or language for each job.

Of course, no approach is perfect for every situation. In the case of microservices and micro-frontends, development teams sometimes face significant challenges to getting the value they expected. These include:

• Specialized and scarce talent: Even today, over half (53%) of IT executives and developers know little about cloud-native development. And many teams find it even harder to fill critical yet highly specialized roles, such as cloud architects.
• Complexity: Breaking a system into several different pieces naturally comes with extra complexity, namely planning and managing dependencies, service discovery, versioning, data consistency, and data transactions across multiple systems. At a time when developers manage up to 100 times as much code as they did a decade ago, this additional complexity can be a deal-breaker for already overstressed teams.
• Chain of responsibility: With everything split into smaller pieces, who remains in charge of keeping the whole system healthy and making sure everything works together? In too many cases, the answer to this question is unclear or unknown.
• Performance: A distributed computing environment often creates challenges around latency for service requests. While it's possible to plan for and mitigate latency challenges, there's no way to eliminate them entirely.
• Security risk: Creating multiple services means a larger attack surface and more pieces for an IT security team to protect.
• Isolation: While microservices can run in separate containers, micro-frontends run in the same browser and share the same styles, memory, browser cookies, and local storage. This means that, although frontend dev teams are not actually working with true isolation, they still need to make sure that every micro-frontend looks right, works right, and delivers a consistent quality of experience.
• Payload size: Related to the lack of isolation discussed in the previous point, developer teams have to face performance penalties as all the resources of the different parts of the system are now competing for the same browser requests. Those problems can actually get worse when development teams start using different tools and frameworks.

One last consideration is maturity. Microservices have been around for a while, but microfrontends don’t yet have the same buy-in, testing, and optimization. Companies like Spotify, Ikea, and Starbucks have seen promising early results, but these companies have an important advantage: they attract top-tier developers with the skill sets and experience to handle these complex technologies. For most organizations, it’s probably better to take a wait-and-see approach to ensure successful adoption in the long run.

One Size Does Not Fit All: Tips for Assessing a Loosely Coupled Approach

A loosely coupled architecture isn't necessarily a solution to all your cloud-native development challenges. It's important to understand whether your team is set up for success with a loosely coupled approach or when it's better to take a pass, at least for now.

Three key questions can give you a much better sense of whether to adopt a loosely coupled architecture for your cloud-native development and how far to go with the process of decoupling your apps:

• What does your organization look like? The number of teams working in an organization, and differences in their pace of delivery, can have a big impact on how much complexity you'll have to contend with. Remember: one of the key advantages of these technologies is promoting agile teams that can work and deliver independently.
• How mature are your teams in terms of toolset expertise and relevant experience? This isn't a question of talent or commitment; the fact is, teams composed of DevOps veterans and highly trained specialists are better equipped to deal with the inherent complexity of a loosely coupled architecture compared to those just discovering these new ways of working.
• What are you trying to accomplish? This question sounds obvious, but it is often overlooked: how many applications are you building? How complex are they, and how many dependencies are involved today?

An Approach to Consider for Achieving DevOps Excellence

Low-code development offers many of the benefits of a loosely coupled architecture and other DevOps technical capabilities — boosting a team's agility and productivity and setting them up for success at scale while minimizing complexity and other potential obstacles mentioned before.

A low-code application development platform can bring a number of capabilities together to maximize the benefits of a loosely coupled architecture while minimizing or even eliminating the downsides. These capabilities include:

• An abstracted and visual, full-stack programming language: In many cases, with a single click, a developer can use low-code to generate all the necessary microservices and frontends that are packaged and deployed as isolated containers that will run in a cloud infrastructure.
• Automated service discovery: Teams are able to simply use actions from another service, and the platform handles service discovery and managing dependencies for you. In runtime, the platform routes to the correct endpoints, regardless of the way a service is distributed.
• End-to-end security: A low-code development platform can deliver end-to-end security by design and by default, from authorization and authentication to things like CDN for DDoS, intrusion detection (IDS), intelligent threat detection (GuardDuty), and data encryption, just to name a few capabilities. It can also incorporate compliance with security standards, including SOC 2, HIPAA, and PCI.

Imagine a solution that enables your dev team to generate thousands of lines of code automatically without having to worry about any of these productivity-killing complexities? That's what a low-code approach offers, and it's why so many teams find it valuable.

As we noted earlier, there's no one-size-fits-all approach to adopting cloud-native technologies. But one of the best things about a low-code solution is that you can learn for yourself whether it's the right approach for your team. If you'd like to learn more, you can give OutSystems low-code development platform a try for free. Or you can talk to an expert. We would love to continue the conversation.