How can you avoid technical debt when refactoring code?

Planning is probably the most important part of the whole process when it comes to refactoring code as there is a much higher potential for causing problems elsewhere in code which depends on the area you're refactoring. This includes both how you intend to make and validate the changes, but also how you choose which changes to make in the first place.

Planning and setting clear goals for the refactoring effort are super important: understanding what you want to achieve and how it aligns with the project’s overall architecture. - Start by writing comprehensive tests to ensure the existing functionality works correctly. That will be a safety net. - Then, refactor in small and incremental steps. Breaking down refactoring into small steps will help improve without introducing new issues. - Collaborate with team members to review code changes before merging them. - Keep the SOLID Principles in mind to design clean and maintainable code and keep documentation up-to-date. - Avoid over-engineering and focus on addressing specific issues. - Keep an eye on the performance of your application.

Refactoring the code is a continuous process to keep up with growing technologies. Hence tech debt is something that we cannot avoid. A few things that I find helpful are - Always have a test suite to run and validate your changes. - Breakdown the code into smaller chunks for refactoring and avoid extensive modifications. This will avoid introducing new issues in the code - Run performance test to validate the quality of refactored code - Always have a working release to fall back on if something goes wrong - Get your code reviewed from peers to get a different perspective and have a brainstorming session to get a more efficient solution - Always make sure you not just test the code that is changed but also the code consumer.

One man's tech debt is another man's treasure. I believe code is always tech debt in some sense, because outside requirements and frameworks change. What's good today might not be good tomorrow. Having a clear goal is really important to evaluate (proposed) changes.

Planning is really key for success as refactoring doesn't solve all the problems, planning will help us to focus as well as known what's left.

Having a strict coding standard and following it can save you a tremendous amount of time in the future but forces you to write "quality code" (extensibility, maintainability, readability, etc.) from the beginning, which can (and will) slow you down (the more so if you have junior devs on the team). You should use the "right" standard for your project. If you need to validate an idea quickly, pull off a one-off microsite or simply get something up ASAP, don't bother with strict CS and just deliver. You'll be rewriting it later, anyway, if it sticks. For a mature project (i.e. something you know will still be around in a couple of years), I would go exactly the opposite way - strict CS will help to keep your project "healthy" long-term.

Coding Standards should never for name sake, like having PMD or sonar qube rules that must be followed.It should be something that touches the actual aspects of Readability and extendability which helps fellow coders and peers. I remember seeing one awesome code which had zero documentation but still the way it was written was just bespoken, hence it should be something that can be practiced naturally with the process other than forcing it as an aspect of your release ceremony ??

Try to make the code readable for any other programmer, while making the code "Cool" and using a complex architecture seems tempting, it is not usually required, it is a "gold mine" for bugs, and unless it's a known thing in your company (e.g an architecture which all Engineers know and follow), it could be frustrating for other developers to understand your code. Using known consistent, paradigms, design patterns, coding styles and best practices helps to collaborate between developers and reduce friction

Language native coding standards are the essence of years of lessons learned from previous programmers. Other coding standards may become in some situations as much of a burden as an aid, e.g. by disallowing language features. Therefore, it is always important to understand not only the standards but their intent to become a better programmer and benefit from them. In the end not all rules of a guideline may suit a given team/project, but a clear subset should be defined and shared within each team. An excellent example for such a language native rule set are the C++ Core guidelines.

Coding standards are important. Ideally, formatting shouldn't be of any concern. Code on developer machines should be formatted in their preferred way and when it's pushed to git it should be formatted by a pre-commit hook or another mechanism in such a way that the upstream code has always the same formatting.

Refactoring tools are invaluable companions for developers, helping them streamline code improvements with precision and confidence. Enhanced Productivity. By simplifying complex refactorings and providing shortcuts, these tools boost developer productivity. Error Prevention. Refactoring tools can detect potential issues during the refactoring process, reducing the risk of introducing new bugs. They offer safety nets, such as automated tests, to verify that code modifications don't break existing functionality. Refactoring tools not only expedite the refactoring process but also elevate the overall quality and maintainability of codebases.

A general rule of thumb for refactoring code is, if it can be automatized a computer should do it. This limits mistakes and is a vital aid. Therefore refactoring tools, automated code formatters, and static code analysis tools can become essential tools for any programmer.

Imagine standing on the edge of a cliff, blindfolded. That's what refactoring without tests feels like. Each line of code you touch becomes a step into the unknown. Will it work? Will something break? Testing isn't just a safety net; it's the roadmap that guides us through the intricate maze of code. Without it, even the smallest change becomes a leap of faith. But with a robust testing framework, refactoring transforms from a daunting task into a systematic process. It's the difference between wandering in the dark and confidently navigating with a clear path ahead. In essence, if you're thinking of refactoring, ensure your tests are in place first. It's not just best practice; it's peace of mind.

Testing is the unsung hero of code refactoring. At the very least, before starting the refactoring process, you should have a test plan. Ideally, you've been building up tests in close concert with your codebase, but that isn't always possible - if you don't have tests beforehand, you should be building tests now. When the refactor is finished, your tests will be able to point the finger at any mistakes or errors in your refactor - and they will happen!

One thing that helped us a lot was the implementation of nightly CI/CD pipelines and builds. Sometimes, it's not your code that disrupts the functionality of your product, but rather the dependencies within other modules and libraries(i.e. kernel modules and python libraries) that result in malfunctions in the final product. Utilizing nightly builds and running unit tests every night can effectively prevent such circumstances.

You cannot do refactoring without having tests in place. Without tests there is no chance to detect a change in behavior after changing things. Besides, testing is also important for each update of any dependency since this might introduce changes.

Skipping tests after even minor refactoring can lead to major issues. Prioritize testing, no matter how minor the change. It's a small investment of time that can prevent significant future problems.

Code reviews are critical for all types of code changes, but particularly when refactoring to reduce the risk of unintended changes to functionality and the introduction of new bugs in the changed code. Including automated tools such as code inspection and test validation ensures the updated code adheres to standards, however there is no substitute for human reviewers. For more complex changes including a code walkthrough is useful as the act of explaining how something functions step by step can help both parties gain a deeper understanding and more easily spot potential issues and edge cases.

Ideally, you'll have a CI/CD pipeline that will make sure most of the common mistakes coders make (EG not adding semicolons if your standards want them). The "CI is the bad guy" is a common way to make sure you don't get discontent between developers! But not everything can be automatically, which is where the code review comes in. It's a good way to catch mistakes/future errors early, and get team buy in on code that's being written. Programming is, after all, a team sport!

Involve your team in the refactoring process. Code reviews provide valuable feedback, catch potential issues, and ensure that refactored code aligns with coding standards and best practices.

"Nobody is perfect" is true everywhere in life. In every team, learning from each other is a key to success as it multiplies your workforce and/or it's quality. Furthermore, local design decisions should be verified in a team to adhere to the initial plan and be adapted as necessary. If refactoring is indeed done in small modularized chunks, multiple people should always review any refactored code. Otherwise, after the last refactoring is just before the next (immediate) refactoring.

Don't just review your code. Get your code REVIEWED by others. Both parties learn in that area and discussing the options helps you see what's possible and what's efficient. Yes, tools like code linters and tests benefit code quality and avoid some tech debt, but nothing gives a view of the consequences of code changes like a discussion with a peer.

It is absolutely necessary to have a check on the libraries and their latest releases. It is best to keep our code up to date for all the critical libraries. If this step is delayed, then the amount of code to be refactored increases which directly increases the risk of breaking the code.

At MRS Technologies, we've found a balanced approach to code maintenance. While we dedicate parts of our sprint to introducing new features and addressing bug fixes, we also ensure a portion is set aside specifically for refactoring. This blend has proven effective. For any team with a culture of continuous refactoring, automation testing is indispensable. Without it, refactoring can become a lengthy and frustrating process. By allocating time for maintenance and having automated tests in place, we not only innovate but also ensure our codebase remains robust and efficient. It's all about striking the right balance.

Break down the refactoring process into small, manageable increments. Each refactoring step should be minimal in scope and should not introduce new features or changes unrelated to the immediate goal. This reduces the risk of introducing bugs.

Make sure the refactor can be done incrementally. Meaning, you can still work on, and release code while doing the refactoring the background. This ensures that you don’t block the existing workflow. This could be done using a pattern like strangler pattern or something similar.

Simplicity is always the best way to refactor some code, sounds wrong but to ensure something is going to work after the refactoring you will have to duplicate functionalities. If your project lacks of test cases so this will be a good approach.

Modularity. When adding some new capability to an existing project, do so as opaquely as possible to the functionality already existing in that project: Pass content back and forth via a half a dozen (or so) calls into the module, and make sure that none of the implementation details of your module get out to the calling code. If they do, they will suddenly become API that somebody else will come to depend on and you can no longer change (debt). This way it stays easy to see where the lines are: if your module doesn't get traction, it is simple to cut it loose. Bonus: if possible module-ify some of the calling code, to reduce its debt.

Good and famous principles are not just some names to memorize and bragging. They are really beneficial if used wisely. For example, SOLID makes your code cleaner and more maintainable and scalable. DRY is a must. KISS is a mandatory. YAGNI is an experience you will tell the others when you find yourself in a bad situation by not obeying it. Learn these and use them well.