Quality from an architectural perspective

The distinction between functional and quality requirements is a given in software development - but what if this taxonomy is the problem? While some insist that performance, security and usability drive the architecture, practice shows that even functional changes can shake entire systems if the architecture is not prepared for them. The real question is not which requirements are more important, but how software can be designed in such a way that it can react to changes of any kind - without every new requirement becoming an expensive rebuild.

Podcast Episode: Quality from an architectural perspective

Are quality requirements the same as non-functional requirements? And what are functional requirements? What is included in the ISO 25010 quality model? And how do you determine if the requirements are met? In this episode, Mike and Alex discuss the concept of quality from a software architecture perspective.

“Many systems are not changed because they are difficult to change.” - Alexander Lorz, Michael Sperber

Dr.-Ing. Alexander Lorz, a freelance software architecture trainer and IT consultant, contributes to the development of the iSAQB Foundation curriculum and creates training materials. With experience in research and industry, he has specialized in practice-oriented software architecture training for various industries since 2016. His goal is to empower teams to deliver high-quality software.

Dr. Michael Sperber is Managing Director of Active Group GmbH. He is an internationally recognized expert in functional programming and has written numerous articles and books on the subject. Michael Sperber is co-founder of the blog

Highlights der Episode

• Functional requirements are architecturally just as relevant as quality requirements - the separation is artificial.
• Maintainability as an architectural focus beats making “important” unchangeable decisions at the beginning.
• Quality requirements without a business case produce unrealistic numbers that nobody can fulfill.
• ISO 25010 is the bible for testers, but an unclear taxonomy problem for architects.
• Functional programming produces an order of magnitude less coupling than object-oriented architecture.

Quality in architecture: measurement, challenges & adaptability

In this episode, my guests Alexander Lorz and Michael Sperber discuss the complex aspects of quality in architecture, the challenges of defining and measuring quality requirements and the importance of adaptability in software architectures.

An exciting debate

In this episode, Alexander Lorz and Michael Sperber, experienced ISAQB trainers for software architecture, are my guests. Together we dive into the topic: What exactly does quality mean from the perspective of architecture? The exchange promises to shed light on the often elusive concepts of functional and quality requirements.

In search of a definition of quality

Defining quality in architecture is proving to be a complex challenge. Our guests share their insights on how difficult it is to tangibly define quality and make it measurable. They shed light on the difference between functional requirements and quality requirements and explain why the latter are often underestimated. This approach means that architects face particular challenges when planning and evaluating projects.

The role of quality requirements in the curriculum

A central point of our discussion is the revision of the ISAQB curriculum, in particular the section on quality. This project reveals the difficulties in dealing with the topic of quality within the training of software architects. It becomes clear that a clear delineation and treatment of quality requirements is essential in order to better prepare future architects for their tasks.

The challenge of quality measurability

How do you measure quality? This is a question that our guests are very interested in. The discussion shows that the measurability of non-functional requirements such as usability or security is a major challenge. Alexander and Michael share their experiences of dealing with such requirements in projects and how important a conscious approach to them is for the overall quality of a system.

Adaptability as a key quality

Another important aspect of our debate concerns the adaptability of software architectures. The ability to respond to change - whether through evolving functional requirements or new frameworks - is emphasized as a critical component for long-term successful projects. Michael shares his experience that flexible architectures are often better equipped to maintain quality standards over time.

Community work on the curriculum

We conclude our discussion with a look at the open development process of the ISAQB curriculum on GitHub. Alexander encourages the community to actively participate in the further development of the curriculum. This call underlines the collaborative effort to continuously improve and adapt teaching around software architecture.