Refactoring vs. Rewrite: What Option to Choose and When?
It is inevitable. At some point in time, most business stakeholders and their IT teams will need to make a critical decision: whether to invest in refactoring the legacy code or completely rewrite it.
The debate between refactoring or rewriting has been an ongoing struggle in the IT world for years. Yet, there is still no perfect answer. One of the leading indicators that could help you decide whether to rewrite or refactor is the size of your technical debt. However, the ultimate decision should be based on a number of different factors.
Keep reading to discover the difference between refactoring and rewriting and how to make the right decision for your business.
Key Triggers to Think about Refactoring or Rewriting
Several key triggers can indicate whether you should rewrite or refactor your code.
First of all, you might have issues with slow loading times, high resource utilization, or frequent crashes, and therefore, lousy technology performance. Your applications may not be secure enough and may even be vulnerable to attacks or breaches. Accumulation of technical debt, with issues such as bloated or duplicated code, lack of documentation, inefficient algorithms, outdated libraries, etc., is yet another reason to refactor vs rewrite.
One more indication that it is time to update your code is when the existing codebase is no longer suitable or efficient for your business needs. In case it is challenging to maintain or extend it, this is a sign that it may be time to rewrite or refactor code in order to improve the maintainability and extendability of the application.
What Is Refactoring?
Refactoring is a process of changing the code and making its internal structure slightly more optimized, modernized, and compliant with coding standards, all while keeping the external behavior the same. The goal is not to make a massive change in how the code works, but rather to make it more efficient and readable, compatible with new features, convenient to work with, and easy to integrate with newer platforms.
As the IT team develops, they may add comments, duplicate code, create shortcuts, large classes, and more. These are known as code smells. They hinder the process of interaction with a codebase, and prevent further improvements and app modernization processes. When software engineers execute refactoring, they iteratively clean up the code by making minor changes to small parts of it. Although this may not make a huge difference in how it operates, cleaning up parts of the original code can result in effectively modernized applications.
Refactoring can be executed anytime – even as a part of your daily programming operations. It can be as simple as renaming, extracting, or moving some elements around in the original environment. Doing this on a regular basis will keep the code freshly updated, which can delay the need for a full-scale application modernization.
Advantages of Refactoring
Refactoring is a great option for many reasons. Some of them include:
Enhanced code quality
Refactoring can improve the overall quality of the codebase by removing redundant or unnecessary code, eliminating code smells, and improving the overall code design. This leads to better performance, higher-quality codebase, and easier testing. It also helps to ensure that the codebase is more reliable and less prone to errors or bugs.
Debugging the legacy code can take hours to understand at first. Refactored code is typically easier to maintain and modify as it is more modular and better organized. It helps reduce the time and effort needed to make changes to the codebase and to fix errors in the future.
Decreased time and costs
Because refactoring only requires working with parts of the existing code without changing the external features it delivers, it takes less time and allows for savings in the budget. This results in less time spent on downtime and disruption of business processes, and frees up the software development team’s time to work on other priorities.
By making the code easier to understand and maintain, refactoring facilitates team collaboration on a codebase. This enhances developers’ productivity, makes cooperation more efficient, and helps your team deliver results quicker.
Disadvantages of Refactoring
While code refactoring has many benefits, there are also some potential disadvantages that should be considered. These include:
If you choose to go with the refactoring strategy, you can improve pieces of code and keep it manageable without major repairments – but that is it. You cannot add new functionality or fix app architecture problems. In other words, you can only improve what already exists. For example, if your code is written in an outdated language and has a monolithic structure, it will still be written in that language and will still have the same structure at the end of the process.
Moreover, refactoring without a clear set of goals or direction can lead to changes that do not provide meaningful improvements to the codebase and can even make things worse. It is important to have a clear roadmap and to understand what needs to be accomplished through refactoring.
Resistance from team members
When there are hundreds of thousands of code lines to be managed and tested, some team members may feel hesitant and may even oppose this process. They may feel like it is a waste of time and would rather rewrite something modern from scratch on their own terms than periodically “reinvent” something that already exists. Your best talent may feel unmotivated and you risk losing employees.
Time and resource costs
In some cases, refactoring code can be a more time-consuming and resource-intensive process than rewriting – particularly if the codebase is large and tangled. In a situation like that, it makes more sense to rewrite or choose another modernization strategy.
Disruption to development workflows
Refactoring can disrupt software development workflows, particularly if changes are made to the shared code that affects multiple team members. This can require additional communication and coordination to ensure that everyone is on the same page.
What Is Rewriting?
Rather than making incremental changes or improvements to the existing codebase, rewriting is the process of completely re-implementing an existing software system or old application from scratch. This can involve starting from a blank page and designing a new code system or reusing some parts of the existing code while replacing or modifying others.
Rewriting is often done when the existing codebase has become too complex or challenging to maintain, or when the underlying architecture or design is no longer suitable for the system’s needs. Sometimes, rewriting can be done when you want to use new technologies, frameworks, or programming languages that are incompatible with the existing codebase.
Advantages of Rewriting Code
Rewriting comes with risks, but it also provides you with immense opportunities. Here are some of its advantages:
Unlike refactoring, rewriting code can open the door for new possibilities. It allows you to improve the user experience and enter new markets, which can, in turn, expand or markedly improve your business. It also helps to embrace modern technologies and become more competitive.
By starting from scratch, IT specialists can develop their work correctly and conveniently from the beginning, thus avoiding previous mistakes and enabling smoother interactions with the code in the future. It is a chance to optimize and streamline the system’s performance, resulting in faster response times, reduced resource utilization, and improved user experience.
Rewriting can also help to enhance the security of applications. Modernized languages, platforms, and frameworks that are compatible with the latest security requirements ensure better protection from malicious attacks.
Writing code from a clean slate allows developers to do it how they want – to create their own “masterpiece” that they can be proud of. Many engineers or teams prefer working with something that they have developed themselves as it allows them to optimize their creativity and knowledge.
Disadvantages of Rewriting Code
As we already mentioned, opportunities do not come without risk. When it comes to rewriting, here are some potential disadvantages that should be considered:
Takes more time and effort
Rewriting takes a significant amount of time as it requires practically redoing everything that has been built for years. It may even require 2 different teams to work on the project – one for maintaining the existing code and another for creating the new one.
With more people needed to work on the rewrite process during a more extended period of time than refactoring would take, rewriting is expensive. It eliminates the hard work that was invested previously, and takes away time that could be spent on developing and implementing innovative solutions. If the result doesn’t come out with the ROI it was supposed to have, it can be detrimental to the budget.
Rewriting does not guarantee that the code you create will be better than the older one. For example, if you merge code written in different languages incorrectly, it may become even more complicated and difficult to manage. Developers have to make sure that they do not make the new code worse by losing any data or features of the old code.
There is also a risk that the rewriting process may take such a considerable amount of time that it ends up giving your competitors a significant head start and advantage. Or, for example, a risk of your users not being ready to accept changes. Novelties are difficult to adapt to.
As we already mentioned, sometimes it can take 2 teams to rewrite code. In a situation like that, while one team rewrites, builds new systems, and grows, the other team maintains what they were working on previously. This often causes a loss of motivation from the second team and adds problems with communication.
[su_note note_color=”#F0F8FC” radius=”15″]An example of how code rewrite benefited the project is our client Acha – a jewelry & piercing wholesale supplier.
To eliminate legacy software, Acha`s former vendor executed replatforming and moved their website from a cloud-based platform Magento 1 to Magento 2. However, their analysis of Acha’s needs was not deep enough, and it resulted in multiple code smells, bugs, and errors.
When Maven deeply examined Acha’s technology, we knew that rewriting was their best option. Now, halfway through the process, we have already made our client’s performance 5 times better. We helped them to conquer their fear of change and to embrace innovation, which ultimately resulted in bigger revenues and successful business transformations.[/su_note]
Legacy Code and Technical Debt
The ultimate goal of code rewrite vs refactor is to deal with legacy code and technical debt. These concepts often need clarification.
Technical debt is the price that must be paid for future development in order to fix bad maintenance from the past, and to make the code modernized, or at least acceptable to work with. Technical debt accumulates over time and applies to every part of your outdated systems, including code and architecture.
Legacy code may be a part of technical debt. It is just the outdated code itself, which wasn’t updated or used for quite some time.
The size of technical debt is one of the key factors in deciding between refactoring vs rewriting an app. The bigger it is, the more significant changes are needed.
How to Decide Which Approach Is Better for Your Project Now: Refactoring vs Rewriting?
When it comes to deciding on code refactoring vs rewriting, there are no stringent guidelines. The decision comes from a variety of factors.
Refactoring is most likely for you if:
- the project needs minor changes, like fixing a bug or reorganizing the code structure
- the goal is to simply improve the existing system
- you do not want to risk much
Rewriting, on the other hand, is better if:
- you have a huge technical debt that requires large-scale changes
- the goal is to significantly improve performance
- you have the time, budget, and expertise
- you are ready to take the risk
However, to correctly decide between refactoring vs rewrite, you must make a business case and a clear roadmap for both of the options. Count hidden and explicit costs, make a cost-benefit analysis, consider a do-nothing option, break down all the steps you need to take, determine the result you want to receive, the risks, and all the possible details.
Choosing whether to refactor or rewrite is difficult and depends on a variety of factors. However, it all comes down to the size of your technical debt and whether you are ready to commit to deep analyzing, risking, and cooperating with the right service providers.
After 13 years of experience in the market, we at Maven have developed our own method of detailed analysis and planning. This helps us choose the most cost-effective strategy for software rewrite vs refactor in order to help your business increase profitability instead of making unnecessary budget spending. We also know how to execute application modernization 2x faster than competitors, while keeping the same high-quality standard.
If you struggle to determine the right approach, contact us today to help you make the right decision.
How Do You Decide Whether to Refactor or Rewrite a Piece of Code?
To decide between refactoring vs rewrite, you should make a business case and a clear roadmap for both of the options. Count hidden and explicit costs, make a cost-benefit analysis, consider a do-nothing option, break down all the steps you need to take, determine the result you want to receive, the risks, and all the possible details.
Is refactoring more cost-saving than rewriting?
Whether refactoring or rewriting is more cost-saving depends on several factors, including the specific context of the legacy system, the extent of required changes, the available resources, and the desired outcome.
When should you not refactor your code?
You shouldn’t refactor your code if you have unclear requirements, a lack of necessary expertise or resources, and a huge technical debt that would be more efficient to rewrite.
What is an alternative for refactoring?
An alternative to refactoring is rewriting or rebuilding the codebase from scratch.
Can new technologies become a reason to start rewriting?
Yes, the emergence of new technologies can be a valid reason to consider rewriting a system. The specific reasons for this are evolving industry standards and best practices, changing user expectations, high competitiveness, etc.
Do you need refactoring in order to set up a cloud-based product?
Refactoring is not a mandatory process for setting up a cloud-based product, but it can be beneficial in certain cases. The decision depends on factors such as the current state of code, desired cloud architecture, and the specific goals a company aims to achieve.
When is refactoring suitable and profitable?
Refactoring is most likely suitable if the project needs minor changes, the goal is to simply improve the existing system, and the business does not want to risk much.
What are the types of refactoring?
Some common types of refactoring techniques are extracting variables, moving methods or fields, renaming, replacing, and inlining code components.
What is the main difference between refactoring and rearchitecting?
Refactoring focuses on improving the internal structure, design, and quality of the codebase while preserving its external behavior and involves making small, incremental changes to the code without altering the overall architecture or functionality of the system.
Rearchitecting involves making substantial changes to the system’s architecture and design to address fundamental issues, improve scalability, enhance performance, or accommodate new requirements.