These days, Computer Science students are benefitting from a whole new way of learning. Something like legacy code probably seems totally unnecessary – akin, perhaps, to NASCAR drivers first practicing on a horse and buggy. But are these comparisons really warranted? Are there, perhaps, some real benefits to be gained from learning legacy code these days?

The answer is yes. Absolutely. And we will explain why in the sections below. This is but one example of the importance of computer professionals learning about the systems they work with. When people look for software engineering services, they want to deal with real professionals who are skilled at problem solving and have a thorough understanding of how software functions on a fundamental level. And this includes a knowledge of legacy code.

What is legacy code?

The term legacy code refers to outdated technology that was once used by a company for software that has since been updated. For students of computer science, it refers to previous versions of code (or outdated technologies) that are no longer used, and which have been replaced by more updated codes.

What does outdated technology refer to, exactly?

Legacy code can refer to technologies, frameworks, or architectures that are no longer used. One of the obvious issues with legacy code is that there is generally no customer support available for it if people try to use it in the current environment.

Another potential problem with legacy code is the likely incompatibility between it and the systems that it is used with. Contemporary systems and the software they use are usually compatible because they were both made at a certain point in the development process. And when incompatible elements are introduced into newer systems (or vice versa), there is an increasing possibility of bugs entering the system.

Are there positive aspects to legacy code?

Absolutely. Both for professionals and recent graduates, it is essential to gain an understanding of legacy code for several reasons:

• It is still relevant. The majority of modern software is built upon what came before it. In order to gain a thorough understanding of current systems, learning about the building blocks of those systems is essential. It’s like what people say about AI running ahead without us: it is getting to a point where it is smarter than us, and therefore we don’t know how to control it. This shouldn’t happen with software development. 
• Increased possibility for maintenance. If there is a problem using modern software, there is a possibility that experts with only a knowledge of the current version will be able to address it. But this isn’t always going to be the case. Understanding underlying mechanisms can be the key to complex problem-solving that makes for a truly valuable employee.
• Improved ability to create new versions. When you have a thorough understanding of the system that your software is built upon, it makes it much easier to think about future stages in its evolution. Without a solid foundation, you might be creating the equivalent of a new story on a home that is built on a swamp. Take the time to understand the whole process of software evolution, and it will pay dividends.
• Similarly, learning about the history of system architecture is very important. Computer scientists need to know their craft and the different logic that went into the various iterations of these architectures.

The best strategies for learning legacy code

Now that we’ve established why it is that learning legacy code is an essential thing for computer science graduates to do, we should discuss what type of learning approach it would be most effective to take. As this is not necessarily offered as part of degree programs, it is largely up to graduates themselves to take care of.

Start from the beginning

Many people’s instincts would probably be to hash out the process themselves, deconstructing from the most recent version of programs down incrementally. This is not the best way to go about it. A better approach is to go back to the very beginning and try to understand the essential building blocks of code as they developed. If you go in the reverse direction, you could miss something critical.

Give yourself tests

This might sound funny, but it is actually a very useful exercise. You may or may not go into teaching one day yourself, but in any case it is good to see how much you’ve learned by challenging yourself to remember concepts and patterns on your own.

Keep thorough records

Finally, you should keep detailed records of everything you learn. You never know when an idea will come in handy as you build your own code in the future. Plus, keeping thorough documentation will serve you well in life overall.

Something every specialist should do

In conclusion, knowing legacy code is an essential part of being a competent computer scientist. Rather than being like a racecar driver riding a horse and buggy, it is more like learning how your own car parts work so that you can fix them when you break down on the road. If you don’t take the time to do this, you could find yourself stuck in the computational wilderness and not know where to go. Plus, it will make you a better software engineer overall.