An Introduction to the Service Design Pattern in SaaS Software Architecture: Benefits, Risks, & Implementation Tips

An Introduction to the Service Design Pattern in SaaS Software Architecture: Benefits, Risks, & Implementation Tips

An Introduction to the Service Design Pattern in SaaS Software Architecture: Benefits, Risks, & Implementation Tips


SaaS software product development is a complicated process that requires you to pay close attention to the structure of your system.

The service design pattern is a reliable and reusable way to solve a common problem in software design. It is based on several tried-and-true best practices that speed up the development process by making software easier to maintain and less complicated.

The service design pattern gives you a flexible and inexpensive way to organize your software application. It gets your code ready for a distributed, temporally independent, and scalable runtime, but it does a lot more than that.

The real power of the service design pattern comes from an informed structure. This lets you make more flexible applications, reduce development time, and improve system visibility and extensibility.

By using software design patterns, developers can make software that is more stable and easier to maintain.

The main structural pattern used to make architecture modular, flexible, and up-to-date is the service design pattern.

In this article, we’ll look at the service design pattern. We’ll talk about why it’s essential, explain a common mistake that can get you in trouble, and give tips on how to do it well.

What are Design Patterns?

Design patterns are prevalent in every engineering discipline. From civil engineering to chemical engineering to software design, patterns are used to improve system structure, quality, and performance.

One way you can tell the difference between a doctor and a receptionist is by the tools they use to get their jobs done. Similarly, there’s a vast difference between engineers who know design patterns and software structural best practices and developers who learned a programming language from a book in 21 days.

Software architects design the foundation and structure of your system, while developers are like the craftspeople who hang sheet rock and put together pre-designed kitchen cabinets. Both require skill and are extremely valuable, but they are different.

With software development, the tools of the engineer and architect are design patterns, SOLD principles, and system taxonomy design.

Your team may use patterns for architectural service design. You may even get the benefits of reusability, reliability, and maintainability. Or, they may just construct unstructured services in your solution, where you get all the pain but none of the gain.

Design patterns in software development help solve everyday problems that occur when designing software. These patterns are the tools of architects and engineers. They don’t tell you how to write code, but they give you a standard way to solve a problem that keeps coming up in a specific situation. These code styling patterns are the tools of the developers.

For instance, the Gang of Four (GoF) is a classic book about software that describes a robust set of patterns. Even though the book lays out the patterns using Smalltalk, an older programming language, they have spread through the industry and are now used in almost every system. Today, they are the scalpel, forceps, and surgical clamps of every software engineer’s structural design tool belt.

Another example of design tools is from Robert Martin’s PPP book, “Agile Software Development: Principles, Patterns, and Practices.” He lays out SOLID design principles for object-oriented programming (OOP) and organizational patterns that every software architect worth their salt lives by today.

Engineers have already solved many design challenges in software development. For example, the GoF patterns and SOLID principles are so helpful that they are now built into modern programming languages, like the iterator pattern. Other GoF patterns, like the chain of responsibility (COR) pattern, describe structures and algorithms for object-oriented programs at a higher level.

What’s the service design pattern?

Just like any other design pattern, the service design pattern is a proven solution for structuring your code base so you can build robust, flexible, and scalable applications quickly and easily by leveraging a proven approach that works.

But many developers new to service design get burned by a common fallacy or defective mental shortcut. Most beginners meld the organizational and operational concepts of service design.

Services and the service design pattern are as different as the ice cubes in your drink and the ice tray that formed them.

The service design pattern is a design-time concept. It’s your blueprint for building a modular, object-oriented system. The service design pattern divides code into separate sets of behaviors and states that work together to make a whole that makes sense.

On the other hand, services are a run-time concept. They focus on interconnectivity, scalability, and data transfer as your system runs.

The service design pattern lets us realize many of Robert Martin’s PPP book’s organizational patterns that help us package code. There are guides to enable us to figure out what to put inside our services, like the Release-Reuse Equivalency Principle, the Common Closure Principle, and the Common Reuse Principles. In addition, there are guides to help us design how services relate, like the acyclic dependency principle, the stable dependency principle, and the stable abstraction principle.

I’ll get into more details in future posts, but the point here is that these are high-level logical organization concepts for your system.

I see it all the time. Unknowing developers create tangled hairballs of uninformed microservices that don’t follow basic software design patterns, conventions, and practices. They end up producing big balls of mud or alphabet soup structures.

But if architects and engineers use modern best practices to design services, the service design pattern makes for a very flexible, long-lasting, and efficient system.

But you’ll only see the full benefits of run-time microservices when experts design them with the right tools, including the service design pattern and basic principles to package code into logical structures purposefully.

Benefits of the Service Design Pattern

There are many benefits to implementing the service design pattern.

These include reduced development time, improved scalability, and decreased complexity.

All tools have a cost-benefit ratio. If it’s more expensive to use a tool than the value it provides, it makes no sense.

Software tools are no different. One primary problem with massive monolithic systems is complexity, because the more complex your system, the more time and money it costs to design, build, and maintain.

The rising costs of code base size

To make things worse, complexity, like many things, compounds, making it non-linear. And there’s a point, in every system, where the costs outweigh the benefits, and it hurts your bottom line more than it helps.

The service design pattern provides code separation. This way, you can have two smaller code bases with the same amount of code, features, and customer value but at a fraction of the cost. You install a firewall for complexity with the service design pattern.

Safe code base size #1

safe code base size #2

While there are many benefits to the service design pattern, the economics and business viability are way more vital than ancillary benefits like efficiency, scalability, temporal decoupling, and reliability.

Using The Service Design Pattern

Because services need to be coordinated, developers may have to deal with a few problems when they use the service design pattern. This is called service orchestration.

And this presents another nonlinear challenge, but this time instead of size, you’re wrestling with the number of integrations.

The rising costs of service counts

Also, service decomposition requires more design knowledge up front, or you can lose all the side benefits of the service design pattern, like efficiency, scalability, temporal decoupling, and reliability.

Balancing service cost and size

Therefore, you must balance the risks of size and integration points in your service design.

Tips for Implementing The Service Design Pattern

When putting service design patterns into place, it is essential to remember the following tips:

  • Services must be a cohesive grouping of logic and state.
  • Services must be coarse-grained (even microservices). Not too many, not too few, not too big, not too small. Your service sizes and counts have to fall into the Goldilocks zone.
  • Services must also be loosely coupled to accommodate change. This means they should work independently, and structural changes to one service shouldn’t blow up and damage other services.
  • Services should have no feedback cycles. This is a sure way to get into trouble and make things hard to predict, since feedback is the breeding ground for chaos.

If your services are going to run as independent services, you also have to be careful they don’t get chatty because the overhead of network calls can be a killer. You also need to design for reusability, plan for eventual consistency, and have ways to deal with faults in a distributed system.

And this is just the tip of the iceberg when building microservices.


The service design pattern is the bedrock of modern modular system design. It’s a proven, repeatable software architecture that simplifies applications’ design, construction, and maintenance. It’s the industry-standard, reusable solution to common software challenges today.

While not about run-time communication protocols, the service design pattern is a best practice you can use to structure your system.

And while service design has risks, putting service design patterns into place has many benefits. These include reduced development time, improved scalability, and sustainability.

While microservice development can quickly get out of hand and burn developers, the service design pattern will rocket your efficiency, quality, and maintainability if you start with informed, solid, and proven patterns.

Best wishes -Matt

By the way…

Are you experiencing common software challenges? Are you looking for a repeatable, proven, industry-standard software architecture that makes it easier to design, build, and maintain your applications?

Put suitable service design patterns into place and reap the rewards. Service design patterns can help simplify your software challenges, reduce complexity and create efficient, modular systems.

Truth Shield’s architecture assessments are the perfect solution to help you confidently move forward in your service design journey. Our assessments are designed to give you the knowledge and insight needed to ensure you are taking the proper steps today to ensure success. tomorrow.

Begin your journey to success today and give your application the structure it needs. Contact us today for a Truth Shield architecture assessment and get the insights you need to move forward confidently.

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