Refactoring is the process of improving the internal structure of the code without changing its external behavior.
It’s common for project managers to think that developers spending time on "unnecessary" things like code refactoring or restructuring is a waste of time. Their view is that it doesn't directly advance one of the outstanding functional requirements. Whilst this view might technically be true, it’s a fundamental misunderstanding of the Scrum framework.
Scrum emphasizes the need for continuous improvement and welcomes changes that add value. This includes work like refactoring, and whilst it might not deliver value in terms of product results today, it delivers value by preventing future delays and mishaps.
There are two main benefits of code refactoring:
When code is not refactored, it becomes harder to maintain, leading to increased technical debt. Technical debt is the cost of maintaining code that has not been refactored. The longer technical debt is ignored, the more expensive it becomes to maintain the code. Refactoring also leads to better testability and reduces the risk of introducing new bugs.
One way to identify when to refactor is to use code smells. Code smells are indicators that suggest the code may be poorly designed or difficult to maintain. Some common code smells include:
When code smells are identified, it may be time to refactor.
Another way to identify when to refactor is to use metrics. Metrics such as cyclomatic complexity and code coverage can help identify areas of the codebase that may benefit from refactoring.
Refactoring should be integrated into Scrum processes to ensure that it is done consistently and with minimal disruption to the development team.
One way to integrate refactoring into Scrum is to create a Definition of Done (DoD) that includes refactoring. The DoD is a checklist of items that must be completed before a product increment can be considered complete. By including refactoring in the DoD, the development team can ensure that refactoring is done consistently.
Another way to integrate refactoring into Scrum is to use make it a timeboxed event. Timeboxing is a technique that limits the amount of time spent on a task. By timeboxing refactoring, the development team can ensure that it is done within a reasonable timeframe that's accounted for, and therefore will not disrupt the sprint.
Approaching refactoring in Scrum requires a systematic and iterative approach that only works if the entire scrum team is aligned. By following the best practices discussed in this article, teams can improve the quality and maintainability of their code, while also reducing technical debt, saving costs and minimizing the risk of project failure.