Shift Left in Software Quality Engineering: Revolutionizing Product Reliability

Introduction

In the fast-paced world of software development, quality assurance (QA) plays a crucial role in delivering robust and reliable products. One approach gaining traction is the “Shift Left” concept in software quality engineering. Let’s dive into this methodology and understand why it’s becoming increasingly important and how it can be combined with other practices to re-engineer the quality of software products.

What is Shift Left?

Shift Left is a practice in software development that moves testing, quality, and performance evaluation earlier in the development cycle. The name comes from shifting these activities to the left on a timeline or project schedule.

The Traditional QA Model: A Brief Overview

In a traditional agile QA model, we typically see the following stages:

1. Sprint planning
2. Test planning
3. Test design
4. Test execution
5. Defect tracking & resolution
6. Reporting
7. Sprint review
8. Test automation

This model, usually applied in 2–4 week sprints, has several advantages:

• Proactive Testing
• Comprehensive Testing
• Collaboration and Communication
• Clear View of product quality
• Reporting and logging of defects
• Maintenance of quality artifacts

The Problem with the Traditional Approach

Despite its benefits, the traditional QA model has a significant drawback. According to the Rule of 10s in quality assurance, the cost of fixing defects increases exponentially as they progress through the development lifecycle. This means that defects caught in later stages of the model incur much higher costs to resolve.

Rule of 10s

Analyzing the use of the Quality Pyramid

Let’s first understand how the Quality Pyramid works to implement the Shift Left approach. This comprehensive concept starts with a structured approach at the bottom to test the most minor pieces while ultimately shifting to break the system mindset at the peak. It is essential to understand at which level we start re-engineering the software quality and where we want to reach in terms of time, cost, and effort.

The Quality Pyramid consists of:

1. Unit Testing (Base)
2. Component Testing
3. Integration Testing
4. End-to-End Testing
5. Exploratory Testing (Top)

The Quality Pyramid

Combining the Shift Left Approach with Quality Pyramid

The Shift Left methodology is built on the principle that “prevention is better than cure.” It aims to catch defects as early as possible in the development process, thereby reducing costs and improving overall quality.

How we leveraged the Quality Pyramid for re-engineering our quality:

1. Early Detection: Emphasizing unit testing at the base allows for structured testing covering the maximum possible cases at the lowest level.
2. Comprehensive Coverage: Each layer builds upon the previous, ensuring thorough testing.
3. User-Centric Approach: Exploratory testing at the top adopts a user-testing mindset and focuses on non-functional areas like performance and edge cases.

Automation: The Key to Robust Quality Assurance

Automation at all levels is crucial to making this approach feasible. Manual quality engineering alone would be tedious and time-consuming.

Mindset Shift — Quality is Everyone’s Responsibility

We need a paradigm shift to execute this well: “Quality is everyone’s responsibility.” This leads to a new Shift Left approach where developers move left, and Quality Engineers move right in the development process.

Development Team Responsibilities:

1. Own the quality of their code
2. Write and maintain unit test cases
3. Create and maintain automation test cases

Over 80% Unit Test coverage for all our code bases was set as a standard for all our code in repositories. Gradually, this was changed to 100% code coverage for all new code. This implementation was carried out using Sonar Cloud along with code linters for all programming technologies.

This has helped us gain confidence in moving in the right direction. It has positioned us to establish the base of the quality pyramid correctly and has aided in early detection starting from the development phase itself.

Quality Engineering Team Responsibilities:

1. Ensure a holistic approach towards quality for improved product experience
2. Focus on deeper unified testing and non-functional testing
3. Concentrate on exploratory testing

Excellence Pillars

Well, we’ve got the base, but what about the rest? What about problems that could be introduced at the integration stage or behave differently at the systems level (end-to-end)? How do we ensure that our products are responsive enough for all our customers?

There is a possibility of the problem being introduced at every stage, and there has to be a check at all these stages. To focus on various stages and enable quality checks so that problems are detected as early as possible, we at Syngenta Digital established core pillars of excellence for which the quality engineers were responsible. Let’s look at those areas:

1. Test Management: To understand what needs to be done structurally and how it needs to be done. This also served as a knowledge base for automation and avoided flaky tests. We have test management in place for almost all our products
2. Automated Unit Test: Comprehensive unit testing at the code level using open-source frameworks like Playwright, Cypress, and many others.
3. Exploratory Test: Promoting the core idea of experimenting with new tools to identify quality gaps via manual and automation tests. A lot of experimentation on emerging quality technologies like advanced quality frameworks, low code/no code tools, or experimenting with AI within this domain.
4. Unified Testing: Focuses on the customer-centric approach towards quality. Emphasizes the functional aspects of the system as a whole.
5. Non-functional Test: Functional tests alone are insufficient; many non-functional parameters must also be considered. We focused on performance testing in this area, experimenting with multiple open-source tools.

Once these quality pillars are established for the products, they eventually move to the continuous integration pipelines, where they become part of day-to-day activities and changes. Thus, we achieve early detection and keep it as a continuous practice.

Please Note: You always have to keep building and upgrading your quality approach. Think from the perspective of breaking the system as early as possible. Updating your test suite and approaches regularly would be crucial for their effectiveness. You are never done!!

Conclusion

Shifting left in software quality engineering is not just about moving testing earlier in the development cycle. It’s a mindset change that emphasizes quality from the beginning of the software development process. By adopting this approach, utilizing tools like the Quality Pyramid, and embracing automation, organizations can significantly reduce costs, improve product quality, and deliver better software at early stages to avoid the cost of delay.

Remember, in software quality, catching issues early is not just cost-effective — it’s a competitive advantage. And with everyone taking responsibility for quality, we can create more robust, reliable, and user-friendly software products.