Regression Testing for Legacy Software

Regression Testing for Legacy Software

With the growing push for software modernization, legacy software can sometimes get a bad rap. It requires training, can have difficulty syncing with new software deployments, and, due to it being out-of-date, may be very difficult to alter or fix in the case of a breakdown. But many businesses rely on legacy software and have found it easier or more cost effective to face these issues, rather than ditch it for a brand-new application or server process. If your business is planning to rely on its legacy software, whether in its current state or in a data migration, regression testing will help to ensure any changes aren’t resulting in broken code or improperly functioning applications.

How Does Regression Testing Work?

Anytime an update is made to a piece of software, the potential for bugs or a degradation in the overall functionality of the application is created. Updates could come in the form of patches, configurations, or merges, and could even be a simple upgrade to your system OS.

Though you and your team can plan for expected issues when these changes occur, the truth is that many of these incompatibilities won’t be realized until later. For these reasons, regression testing should be completed by a thorough quality assurance team to find what parts of the application are functioning incorrectly or differently. It should also be a collaboration between the QA squad and your developers; QA may be able to show that something is going wrong, but they won’t be able to find out exactly why without diving into the code. Because this is a tedious and continuous task, regression testing can also be automated to allow your QA testers to focus their efforts on more hands-on activities and critical thinking. Software regression testing tools are the team’s best friend in this instance.

How Does Regression Testing Help Maintain Legacy Software?

At its very core, regression testing is designed to ensure nothing has changed and that all parts are functioning the same as before the alteration. In a similar way, a company will decide to stick with legacy software because it’s easiest to use in comparison to a new application or system. For that reason alone, regression testing pairs naturally with a legacy application. Consider your cell phone; whether it’s an Android or iPhone, we’ve probably all gone through the same sense of confusion and frustration when a sudden OS update rolls out. You may have even found yourself saying “Why can’t this just work the way it did before?” Automated software regression testing tools can help ensure the product keeps the same functionality and security for every user, even when you’re merging with a new schema or system.

When Must I Perform Regression Testing?

Regression testing works best when it’s constant, but there are a few key situations when it’s even more necessary than normal:

  • When merging with a new application

Let’s say a credit union is continuing to rely on its megalithic legacy system for customer data. This could be due to its sheer size or a fear of any downtime for customer use. However, the company wants to integrate a new customer service application to better serve its members. When introducing a new piece of code, regression testing will need to be completed in order to confirm that the new app doesn’t impact the legacy system’s operations.

  • When updating to new version of operating system

Even if you are not intentionally changing your applications, the underlying systems they depend upon are changing at an increased pace. This could include anything from the computer systems you’re running on, to the applications like web browsers you use to access it. You will typically see multiple updates per month across Windows 10 Updates, and updates to IE, Chrome and Firefox browsers. If you’re logging into your legacy software via an online portal, you’ll want to be sure you’re set up with automated regression testing that will let you know of any bugs following a software update.

  • When migrating to a new server

Even what seems like a simple migration from an on-premise server to a cloud-based server platform like Azure or Amazon AWS will still require complete regression testing to confirm that external interface connections still work, and that the new system resources (CPU, Storage, Memory) are configured correctly.

Though our technological pace is pushing us toward new applications and systems, legacy software very much still has a place in the business world. However, because it needs to integrate with other pieces of software around it, regression testing is not just recommended – it’s a requirement. If you want to be certain your apps are all functioning as needed, be sure to reach out to iLAB today.