War Story: Why Care About Technical Debt?

In our book “Refactoring for Software Design Smells”, we have included numerous anecdotes on technical debt. Here is a software war story that many readers liked because it related to their experience. [If you are new to technical debt, read this article before you continue.]

To understand the impact that technical debt has on an organization, we present the case of a medium-sized organization and its flagship product. This product has been on the market for about 12 years and has a niche set of loyal customers who have been using the same product for a number of years.

Due to market pressures, the organization that owns the product decides to develop an upgraded version of the product. To be on par with its competitors, the organization wants to launch this product at the earliest. The organization marks this project as extremely important to the organization’s growth, and a team of experienced software architects from outside the organization are called in to help in the design of the upgraded software.

As the team of architects starts to study the existing architecture and design to understand the product, they realize pretty soon that there are major problems plaguing the software. First and foremost, there is a huge technical debt that the software has incurred during its long maintenance phase. Specifically, the software has a monolithic design. Although the software consists of two logical components—client and server—there is just a single code base that is being modified (using appropriate parameters) to either work as a client or as a server. This lack of separation of client and server concerns makes it extremely difficult for the architects to understand the working of the software. When understanding is so difficult, it is not hard to imagine the uncertainty and risk involved in trying to change this software.

The architects realize that the technical debt needs to be repaid before extending the software to support new features. So they execute a number of code analyzers, generate relevant metrics, formulate a plan to refactor the existing software based on those metrics, and present this to the management. However, there is resistance against the idea of refactoring. The managers are very concerned about the impact of change. They are worried that the refactoring will not only break the existing code but also introduce delays in the eventual release of the software. They refer the matter to the development team. The development team seems to be aware of the difficulty in extending the existing code base. However, surprisingly, they seem to accept the quality problems as something natural to a long-lived project. When the architects probe this issue further, they realize that the development team is in fact unaware of the concept of technical debt and the impact that it can have on the software. In fact, some developers are even questioning what refactoring will bring to the project. If the developers had been aware of technical debt and its impact, they could have taken measures to monitor and address the technical debt at regular intervals.

The managers have another concern with the suggestion for refactoring. It turns out that more than 60% of the original developers have left the project, and new people are being hired to replace them. Hence, the managers are understandably extremely reluctant to let the new hires touch the 12-year old code base. Since the existing code base has been successfully running for the last decade, the managers are fearful of allowing the existing code to be restructured.

So, the architects begin to communicate to the development team the adverse impacts of technical debt. Soon, many team members become aware of the cause behind the problems plaguing the software and become convinced that there is a vital need for refactoring before the software can be extended. Slowly, the team starts dividing into pro-refactoring and anti-refactoring groups. The antirefactoring group is not against refactoring per se, but does not want the focus of the current release to be on refactoring. The pro-refactoring group argues that further development would be difficult and error-prone unless some amount of refactoring and restructuring is first carried out.

Eventually, it is decided to stagger the refactoring effort across releases. So, for the current release, it is decided to refactor only one critical portion of the system. Developers are also encouraged to restructure bits of code that they touch during new feature development. On paper, it seems like a good strategy and appears likely to succeed.

However, the extent of the incurred technical debt has been highly underestimated. The design is very tightly coupled. Interfaces for components have not been defined. Multiple responsibilities  have been assigned to components and concerns have not been separated out. At many places, the code lacks encapsulation. As one can easily imagine, each and every refactoring is difficult, error prone, and frustrating. In short, it seems like a nightmare. The team starts to feel that it would be better to rewrite the entire software from scratch.

In the end, in spite of the well laid-out strategy, there is considerable delay in the release of the product. In fact, to reduce further delays in the release, the number of new features in the release is significantly reduced.

So, when the product is eventually released in the market, it is 6 months later than originally planned and with a very small set of new features!

Although the product customers are not happy, they are promised a newer version with an extended set of features in a few months’ time. This is possible because the refactoring performed in the current release positions the design for easier extension in the future. In other words, since part of the debt has been paid (which otherwise could have led the project into technical bankruptcy), it has paved the way for further extension of the product!

(Source: “Refactoring for Software Design Smells: Managing Technical Debt”, Girish Suryanarayana, Ganesh Samarthyam, Tushar Sharma, ISBN – 978-0128013977, Morgan Kaufmann/Elsevier, 2014. URL: http://amzn.com/0128013974)

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