KISS in the IT Industry

In the IT industry, the acronym KISS can be interpreted in different ways, but ultimately it always conveys the same core idea. Some translate it as “Keep it simple and stupid,” which essentially means: make things as simple as possible so that everyone can understand them. Others prefer a slightly more elegant interpretation, “Keep it simple and smart,” which roughly translates to keeping things straightforward and intelligent.

How does the KISS principle apply to software development?

In software development, the goal is no longer just to write code that works. It is about creating solutions that are sustainable, understandable, and maintainable. Martin Fowler, a pioneer of the Clean Code movement, captures this idea perfectly when he says: “Any fool can write code that a computer understands. Good programmers write code that humans understand.”

This quote highlights the importance of readability and clarity in code, because ultimately it is people who have to maintain, extend, and improve it. Even in the age of artificial intelligence, this requirement remains unchanged: code should be written in a way that is as understandable as possible for humans, since they are the ones who will maintain it and fix issues when problems arise.

Is this principle always followed in practice?

Unfortunately, the answer is no. Throughout my career, I have met many brilliant IT professionals who were exceptional programmers but still produced code that was difficult to read. One possible reason is that they may not have been aware of how complex code that seems trivial to them can appear to others. In some cases, it even felt as though they wanted to demonstrate their mastery of the latest programming techniques, regardless of whether using those techniques actually made sense in the given situation.

What does this mean in concrete terms?

In software development, simplicity is often the key to long-term success. Complex solutions may look impressive at first glance, but they carry significant risks when it comes to maintenance, extensibility, and comprehensibility. This is where Occam’s Razor applies: “Entities should not be multiplied beyond necessity.” In other words, when there are multiple possible solutions, the simplest one should be preferred. Good developers therefore do not strive for the most complicated solution, but for the most elegant one.

Is it always easy to implement this approach?

Paradoxically, writing code that is easy to read is not always easy. I have to admit that I am sometimes surprised myself at how hard to read some parts of my own code are when I solved a given task functionally under time pressure. Usually, I try to improve the readability afterward, but I would not recommend this approach, as it can easily lead to technical debt. We all know the situation: when time is short, readability—and therefore maintainability—is often sacrificed just to deliver the required functionality to the customer on time. What many people do not realize is that this effectively means taking out a loan against the future, which later has to be repaid at a high cost in the form of poor maintainability and many additional hours spent on future enhancements and bug fixes.

How can we do better?

We should always place great importance on continuous improvement. Fortunately, most development teams today adopt guidelines based on Clean Code principles, especially in newer projects, resulting in code that is easier to maintain and understand. Readability often takes precedence over cleverness, since code is read far more frequently than it is written. Functions are deliberately kept small and designed to fulfill only one clearly defined responsibility whenever possible. Meaningful names for variables, classes, and methods help ensure that the purpose of the code is immediately recognizable. Every line of code should provide clear value, and unnecessary complexity is avoided wherever possible. Testability also plays a central role, as cleanly structured code can be efficiently validated through tests and is far easier to evolve over time.

Should KISS and Clean Code principles always be applied?

To answer this with one of my favorite phrases as a software architect: it depends. When working with high-level languages such as Java or C#, there is little reason not to use long, meaningful method and variable names, since these are optimized by the compiler anyway. In assembly programming or on IoT devices, however, available memory can be a limiting factor, which sometimes makes the deliberate use of short variable names necessary. That said, unless you are working very close to the hardware, I would personally always recommend adhering to the Clean Code principles and the KISS paradigm as much as possible.