A Step-by-Step Guide to Effective Regression Testing in Software Development

Regression testing is a software test process that is carried out after making changes or upgrades on a software application and retesting the application areas that may have been affected by the fix. Running a specific set of test cases either manually or automatically can accomplish the test.

Regression Testing is done in order to check the software stability following amendments. It is a process of testing that occurs repeatedly to ensure that modifications have not compromised existing functionalities. Mainly, it catches regressions whereby new or regressed bugs are introduced or created through updates.

It is a type of software testing called regression testing that is carried out in order to make sure that after alterations in the existing features, bug fixes, and the addition of new features, the product works as expected.

Regression, therefore, refers to retesting the same sections of the product that have not been altered. Finally, software testers determine whether the changes have caused bugs or defects.

What Is Regression Testing?

Regression testing is a variety of software testing done in software testing in order to find bugs in functionality. Regressions are commonly introduced during code changes to eliminate errors or add new features.

The regression testing ensures that these code changes have not caused collateral effects that could cause undesired results and that the software still has the required functionalities. It is normally conducted once functional testing is complete and before release into production.

There are two main approaches to regression testing: retesting and re-executing. In retesting, the tester reruns the same test cases either manually or with automation on the new build to see whether they are still passing. Re-executing involves the execution of automated test cases for the new build, even if they passed or failed against the previous build.

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It is designed to ensure that the changes made do not create new bugs and that the software performs as intended. It is a critical part of any software development and should be taken with the necessary considerations and attention.

Why is Regression Testing Important?

The right regression test plan should meet a variety of software development requirements. In a nutshell, it provides your testers and QA specialists a chance to explore any issues that may have emerged from the introduction of new code in existing programs or applications.

Some of the other reasons that make it a must-have are as follows:

  • Checks the Effectiveness of New Code.

The application is regression-tested before implementing the new code. Retesting is then done to verify that the application operates normally and as required, even after adding a single line of code.

  • Assures That New Code Does not Affect the Coding Features that Already Exist.

In case a program or application is updated, testers can always do regression testing each time. It will be useful because it makes it possible to see new codes and ensure that they will not adversely affect other program features.

  • Ensures the Adverse Effects of Implementing Software Updates are Monitored.

It detects any defects or bugs following updates. For instance, a mobile game tester may carry out a regression test to determine whether the introduction of a new code leads to unforeseen vulnerabilities or bugs.

  • Enables Retesting

It provides extra test runs for QA evaluations, which ensure the genuineness, feasibility and functionality of changes made to the application’s code. Testers can also retest each and every case in order to see how these changes have affected the program after a software update or change.

Effective Regression Testing in Software Development: A Step-by-Step Guide

Regression testing is an important step of the software development lifecycle. It is a process of testing an application again to ascertain if new changes or updates have affected the working of original functions. Here’s your step-by-step guide to effective regression testing:

  • Understanding the Basics

Regression testing is a quality assurance process aimed at ensuring existing functionalities still work as expected when code changes are made. It catches unforeseen side effects or “regressions” that can occur in new development cycles. However, understanding its importance means that it is not just for fixing the new issues but also for making sure that the old and established features remain intact.

  • Building a Test Suite

Your test suite needs to be thorough, covering every aspect of your software. Imagine it as a bundle of test items that cover the basic functionalities to complex features of your application. Such a suite will be the basis of further regression tests to prevent any vital thing from being tested.

  • Automation is Key

Regression testing must include test automation. Specialized tools and scripts can greatly automate the process and reduce the risk of human errors. Test automation tools include Selenium for web applications and JUnit and TestNG for Java applications. Also, you can employ a cloud-based cross-browser testing platform like LambdaTest. LambdaTest automates your tests on 3000+ browsers and operating systems to show you how your application performs in various environments.”

This addition easily incorporates LambdaTest into the guide, stressing its contribution to the process of regression testing through cross-browser testing.

Furthermore, LambdaTest has screenshot testing, automated visual testing, and integration for well-known testing frameworks. By doing so, it becomes an integral part of your regression testing armory to ensure that your application remains functional and visually pleasing in different environments and setups.

  • Selecting the Right Test Cases

It would not be feasible to execute every test case during every regression test cycle. Start with the most important ones, which are those focused on the main functions and the parts that have been updated recently. It enhances the efficiency of your test resources by focusing on the most critical aspects.

  • Execute Tests Thoroughly

Rigorous execution entails being keen on details. Ensure you closely watch what the software does when you are testing the test cases. If any deviations or strange behavior are detected, investigate and resolve it fully. It is the last step, and it is done to make sure you catch any problems that might be present during testing.

  • Document and Report

Regression testing also requires detailed documentation. Also, make notes of your test results, whether they are correct or incorrect. Document the description of the error and any relevant debugging information when a test case fails. It is important because it provides documentation that helps to trace the quality of your software.

  • Continuous Integration

Regression testing should be automated and built into your CI pipeline in such a way that tests are automatically run whenever a code change is committed. The practice guarantees that the new code is instantaneously validated. It makes it difficult to introduce defects within the codebase and encourages a rapid feedback loop between development and testing.

  • Monitor Performance

The regression testing not only validates the functionality but also can show some performance-related problems. Ensure to monitor the software’s performance metrics through the testing phase to detect any bottlenecks or decline in performance as the code develops.

  • Evolve Your Test Suite

As time continues, your test suit should always grow along with your software. The test suite may need to be expanded with new test cases and updated to remove obsolete features. Staying on top of the test suite means that your testing effort matches the dynamic environment of your software.

  • Implementing Feedback

It is important for you to have open and effective communication with your testing and development team. Issues that are discovered in the regression testing must be communicated, reviewed, and resolved in a timely manner. Feedback from the testers and the developers can also be integrated into the product development process to improve software quality.

By taking these steps in-depth, you create a strong regression testing process for your application. The regression testing procedure will be reliable, support the further development of the application, and will take into account the changing characteristics and features of the application.

What is the Best Practice in Achieving Smooth Regression Testing?

Now it is time to talk about some regression testing best practices that will help you construct an excellent regression strategy and aid your products and services to stand out.

  • Follow The Latest Regression Suite

It means that your teams have to adhere to the latest regression test suites as the expectations of users change and technology evolves. They have to scrutinize the NFRs/FRRs and prioritize the test cases after that.

  • Regularly Update Your Regression Pack

A regression pack is a combination of test cases that run when the software is modified. It is readily integrated with Ad-hoc or random tests. This pack needs to be updated to ensure that there are no possible bugs in the real, controlled environment.

  • Watch Out For the Busy Paths.

Looking out for highly-trafficked paths will allow you to integrate into your app some functionalities and features. One needs to know the target group, their collaborations, and what they like about the standard highlights and attributes.

  • Run a Full Regression Suite Only When Necessary.

Not all builds will require a full regression suite. For a minor release, you can smoke test and run a specific regression test for a module that has been modified. In addition, AUT can also be helpful when sorting tests in order.

  • Repeat Test Cases

It would be beneficial to use tests that have previously detected errors and glitches in the regression packs. Authenticity can also be ascertained by executing the tests that the program passes very easily.

  • Be Data-Driven

Create a culture of using datasets to boost the effectiveness of your regression testing environment. Thus, you will avoid redundancy, develop lightweight scripts, keep data as a database easier to manage, etc.

  • Closely Observe Changes

Software development is the only constant change. Therefore, you need to take all the serious alterations or adjustments as important. Ensure that you work with your developers, testers and QA professionals and gain first-hand knowledge of the new upgraded version as well as any changes.

  • Use a Diversified Automation Toolkit

You must employ appropriate instruments and technology that will expand test coverage, provide numerous testing chances, and allow you to explore your desired scripted language at its maximum capacity.


In conclusion, this guide provides valuable insights into the significance of regression testing and its pivotal role in elevating software quality. By integrating regression testing into your development process, you can detect and address issues at their nascent stages, preventing them from escalating into more complex problems later on. As you embark on this journey of software improvement, remember that your toolkit is just as essential as your testing strategy. 

Cloud-based solutions like LambdaTest offer a streamlined approach to regression testing, allowing you to automate tests across diverse browsers and operating systems. With features like screenshot testing, automated visual testing, and seamless integration with popular testing frameworks, LambdaTest becomes a valuable ally in ensuring your software consistently delivers the highest quality and reliability.