Overview
One of the most challenging aspects of Agile development is determining how to slice a feature set into manageable pieces. The two primary approaches to slicing are vertical and horizontal slicing.
In this post, we'll examine the benefits and drawbacks of both vertical and horizontal slicing, using factual data to provide an unbiased comparison.
So, let's start slicing!
Vertical Slicing
Vertical slicing, also known as feature slicing, is the process of dividing a feature into small, vertical slices that deliver value independently. Each vertical slice contains all the layers of the application, from the frontend to the backend.
The primary benefit of vertical slicing is that it delivers value to the customers and end-users quickly. This ensures fast customer feedback and early detection of any issues. It also simplifies testing and reduces waste, as only the relevant code is tested.
However, vertical slicing has one significant drawback - it can lead to technical debt. This is because each slice contains all the layers of the application. A poorly written vertical slice will inevitably result in poor code quality for the entire codebase. Furthermore, this approach can make it challenging to optimize code performance, as each slice may have its unique set of performance issues.
Horizontal Slicing
Horizontal slicing is the process of slicing a feature set horizontally across all the layers of the application. Each slice delivers a specific layer of functionality. For example, a slice may deliver a user interface component or a database schema.
The primary benefit of horizontal slicing is that it helps ensure code quality across all layers of the application. Each slice delivers a clean, optimized code that adheres to the best practices of that specific layer. Furthermore, horizontal slicing can simplify testing since the code is optimized for specific layers.
However, a significant drawback of horizontal slicing is that it may take time before the end-user receives value. Since each slice only delivers a layer of functionality, the functionality required for delivering immediate value may take several iterations to achieve. This can lead to extended development schedules and slower customer feedback. Furthermore, this approach may result in over-optimized code with unnecessary complexity in the codebase.
Which Approach is Better for Agile Development?
We can't say which method is superior, as both vertical and horizontal slicing have strengths and weaknesses. The choice of approach depends on the specific requirements of the project, including the complexity of the feature set, end-user feedback, and code optimization goals.
A well-balanced approach to slicing should take into account the specific requirements of the project and the expertise of the development team.
Conclusion
In conclusion, both vertical and horizontal slicing methods have unique advantages and disadvantages. Choosing the best approach requires the development team to consider the requirements of the project and create a well-balanced slicing strategy.
We hope this post has provided valuable insights into the two primary slicing methodologies, and you have enjoyed reading through it.
References
- Building the Right Thing the Right Way with Agile Feature Slicing. (n.d.). Retrieved October 15, 2021, from https://spin.atomicobject.com/2018/10/26/agile-feature-slicing/
- Meyerovich, L. (2014, January 23). Vertical Slice Architecture. Retrieved October 15, 2021, from https://martinfowler.com/bliki/VerticalSlice.html
- Fowler, M. (2017, May 16). Horizontal vs. Vertical Scaling. Retrieved October 15, 2021, from https://martinfowler.com/articles/scaling-up-down.html