August 24, 2020

Using Gauge for regression testing

Migration using regression testing: A case study

In 2019, a leading Unified Payments Interface (UPI) application needed futureproofing to meet the growing demand for digital payments in India. Migrating the app’s technology stack was critical to creating new opportunities and better engagement. That is when the leadership team overseeing the payment application decided to partner with ThoughtWorks. The fundamental tenets of the collaboration were to transform functionality, improve customer satisfaction, and gain competitive advantage. The new co-sourced team in-charge of driving this project included developers, testers, designers, and DevOps experts. Recently, we spoke with Kala Singh and Biswajit Pattanayak of the team to gain insights into how testing played a crucial role in successfully migrating the UPI application.

Project Manager Kala drove collaboration, managed stakeholders, and ensured that the team achieved targeted outcomes. Quality Analyst Biswajit played a crucial role in testing rapid code releases and bringing in best practices to the testing process.

Challenge: A migration without disruptions to usability and experience

Amidst mushrooming UPI payment providers, the app had to enhance usability, performance, and create market differentiation. This meant migrating from a custom application framework to React Native and introducing new features, front-end enhancements, and seamless integration with third-party plugins. But the team ensured that new releases did not impact the app’s functioning. Several releases were pushed to production frequently, without affecting its millions of users. To achieve this, testing had to be top-notch, and the team embraced new techniques to deliver quality at speed. Additionally, software was overhauled as the new coding environment used Java and Appium.

Solution: Regression testing

With around 12 years of testing experience, and 10 years in automation testing, Biswajit saw that the testing team needed a regression suite to ensure that code changes did not affect existing features.

At the start of the project, Kala and Biswajit realized that test automation could speed up deployments. Biswajit recollects,

As the project pushed a series of code releases to production rapidly, we had to ensure that the software worked seamlessly.

Biswajit evaluated Behavior Driven Development (BDD) tools like Cucumber and JBehave. However, his experience with Gherkin’s prescriptive syntax made him look for less restrictive options. At this time, he learned of Gauge from his colleagues. Gauge, an open source test automation framework from ThoughtWorks, is built on test case reusability using plain markdown syntax. Biswajit says,

As a first step, we analyzed the pros and cons of using Gauge. Its easy-to-use features and test writing and management capability made it the right tool for regression testing on this project.

Kala adds,

As Gauge was open source, it aligned with the culture at UPI application’s team.

Initially, Biswajit trained the testers on automation testing with Gauge, and they were quick to learn. Gauge soon proved valuable in automating sanity testing. For instance, Gauge automated testing scenarios that ensured every transaction on the app did not exceed a set limit. Also, by automating sanity testing, the team validated that the ‘Bill Pay' functionality worked seamlessly. Finally, automated test scripts helped them catch regressions around integrations like the users selecting a bank account.

Biswajit highlights three Gauge features that transformed regression testing:


A concept, within Gauge, presents a business intent summary by combining logical groups of actions. Concepts provide the ability to combine reusable, logical groups of steps into a single unit. Biswajit adds,

It was an important and useful feature that allowed the team to fast-track testing scenarios, such as when users wanted to send money to their favorite contacts.

Data-driven test execution

Gauge's data table feature enabled the team to reuse and create test cases quickly. Data tables for a specification were also easily imported from an external CSV file.


Environments variables are a set of dynamic-named values that affect how tests act in an operating system. Biswajit elaborates,

Gauge allowed us to set specific environment variables for iOS and Android mobile operating systems, making it easy and quick to run specifications anytime.

Benefits: Transformation in testing

Today, the app has migrated successfully. The team has also released new features within weeks, such as finding merchants for home deliveries, donating to the PM Care Fund, and displaying COVID-related information on the app. Gauge played a crucial role in ensuring effective regression testing for the UPI-driven payments app. Kala and Biswajit are confident that Gauge helps the testing culture within the payment’s app team and will continue to drive value across the software development process.