The Essentials of Modern Software Engineering. Ivar Jacobson
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2.2.4 Consequences
There is a methods war going on out there. It started 50 years ago, and it still goes on. Jokingly, we can call it the Fifty Years’ War, and there is still no truce. In fact, there are no signs that this will stop by itself.
• With every major paradigm shift such as the shift from structured methods to component methods and from the latter to the agile methods, basically the industry throws out all they know about software engineering and starts all over with new terminology with little relation to the old. Old practices are viewed as irrelevant and new practices are hyped. To make this transition from the old to the new is extremely costly to the software industry in the form of training, coaching, and change of tooling.
• With every major technical innovation, for instance cloud computing, requiring a new set of practices, the method authors also “reinvent the wheel.” Although the costs are not as huge as in the previous point, since some of the changes are not fundamental across everything we do (it is no paradigm shift) and thus the impact is limited to, for instance, cloud development, there is still foolish waste.
• Within every software engineering trend there are many competing methods. For instance, back as early as 1990 there were about 30 competing object-oriented methods. When this book was written, there were about 10 competing methods on scaling agile to large organizations; some of the most famous ones are Scaled Agile Framework (SAFe), Disciplined Agile Delivery (DAD), Large Scale Scrum (LeSS), and Scaled Professional Scrum (SPS). They typically include some basic widely used practices such as Scrum, user stories or alternatively use cases, and continuous integration, but the method author has “improved” them—sarcastically stated. There is reuse of ideas, but not reuse of original text, so the original inventor of the practice feels he or she has been robbed of his/her work; there is no collaboration between method authors, but instead they are “at war” as competing brands.
Within these famous methods, there are some often useful practices that are specific for each one. The problem is that all these methods are monolithic, not modular, which means that you cannot easily mix and match practices from different methods. If you select one, you are more or less stuck with it. This is not what teams want, and certainly not their companies. This is, of course, what most method authors whose method is selected like, even if it was never what they intended.
Typically, every recognized method has a founding parent, sometimes more than one parent. If successful, this parent is raised to guru status. The guru more or less dictates what goes into his/her method. Thus, once you have adopted a method, you get the feeling you are in a method prison controlled by the guru of that method. Ivar Jacobson, together with Philippe Kruchten, was once such a guru governing the Unified Process prison. Jacobson realized that this was “the craziest thing in the world,” a situation unworthy in any industry and in particular in such a huge industry as the software industry. To eradicate such unnecessary method wars and method prisons, the SEMAT (Software Engineering Method and Theory) initiative was founded.
2.3 The SEMAT Initiative
As of the writing of this book there are about 20 million software developers6 in the world and the number is growing year by year. It can be guesstimated that there are over 100,000 different methods to develop software, since basically every team has developed their own way of working even if they didn’t describe it explicitly.
Over time, the number of methods is growing much faster than the number of reusable practices. There is no problem with this. In fact, this is what we want to happen, because we want every team or organization to be able to set up its own method. The problem is that until now we have not had any means to really do that. Until now, creating your own method has invited the method author(s) to reinvent everything they liked to change. This has occurred because we haven’t had a solid common ground that we all agreed upon to express our ideas. We didn’t have a common vocabulary to communicate with one another, and we didn’t have a solid set of reusable practices from which we could start creating our own method.
In 2009, several leaders of the software engineering community came together, initiated by Ivar Jacobson, to discuss the future of software engineering. Through that, the SEMAT (Software Engineering And Theory) initiative commenced with two other leaders founding it: Bertrand Mayer and Richard Soley.
The SEMAT call for action in 2009 read as follows.
Software engineering is gravely hampered today by immature practices. Specific problems include:
• The prevalence of fads more typical of fashion industry than of an engineering discipline.
• The lack of a sound, widely accepted theoretical basis.
• The huge number of methods and method variants, with differences little understood and artificially magnified.
• The lack of credible experimental evaluation and validation.
• The split between industry practice and academic research.
We support a process to re-found software engineering based on a solid theory, proven principles, and best practices that:
• Include a kernel of widely agreed elements, extensible for specific uses
• Address both technology and people issues
• Are supported by industry, academia, researchers and users
• Support extension in the face of changing requirements and technology.
This call for action was signed by around 40 thought leaders in the world coming from most areas of software engineering and computer science; 20 companies and about 20 universities have signed it, and more than 2,000 individuals have supported it. You should see the “specific problems” identified earlier as evidence that the software world has severe problems. When it comes to the solution “to re-found software engineering” the keywords here are “a kernel of widely agreed elements,” which is what this book has as a focus.
It was no easy task to get professionals around the world to agree on what software engineering is about, let alone how to do it. It led, of course, to significant controversy. However, the supporters of SEMAT persevered. Never mind that the world is getting more complex, and there is no single answer, but there ought to be some common ground—a kernel.
2.4 Essence: The OMG Standard
After several years of hard work, the underlying language and kernel of software engineering was accepted in June 2014 as a standard by the OMG and it was given the name Essence. As is evident from the call for action, the SEMAT leaders realized already at the very start that a common ground of software engineering (a kernel) needed to be widely accepted. In 2011, after having worked two years together and having reached part of a proposal for a common ground, we evaluated where we were and understood that the best way to get this common ground widely accepted was to get it established as a formal standard from an accredited standards body. The choice fell on OMG. However, it took three more years to get it through the process of standardization. Based upon experience from the users of Essence, it continues to be improved by OMG through a task force assigned to this work.
In the remainder of this part of the book, we will introduce Essence, the key concepts and principles behind Essence, and the value and use cases of Essence. This material is definitely useful for all students and professionals alike. Readers interested in learning more, please see Jacobson et al. [2012, 2013a, 2013b], and Ng [2014].
What Should You Now Be Able to Accomplish?
After studying this chapter, you should be able to:
• explain the meaning of a method (as providing guidance for all the things you need to do when developing and sustaining software);
• explain the meaning of a practice and its types (i.e., solution-related practices, endeavor-related practices, customer-related practices);
• explain the meaning of waterfall methods and their role