Shift Left Testing: Types and Benefits

The IT sector has embraced a software development framework that adheres to a specific sequence of stages:

1. Requirements 
2. Design 
3. Coding 
4. Testing 

This means that testing appears at the end of the development process when read from left to right.

In this article, we will delve into the testing approach known as shift left testing, answer the question “what is shift left testing”, explore the benefits of shift left testing, and discuss its impact on software development.

As time went on, it became increasingly clear that testing plays a crucial role in the development process and should be initiated as early as possible. This shift in understanding came about due to the realization that errors identified late in the software development cycle incurred exorbitant costs. Addressing these issues at the final stages demanded enormous effort and consumed excessive time.

Shift left testing is a proactive approach in software development where testing activities are initiated earlier in the lifecycle. It used to be thought that testing was worth doing at the end of the development process. However, shift left testing moves these tasks to earlier stages, such as during the design or coding phases.

This approach is beneficial for several reasons. Firstly, it is cost-efficient. Detecting and fixing bugs early in the development cycle is cheaper and less time-consuming than addressing them later. This early detection ensures improved quality, as issues are caught sooner, leading to a more stable and reliable product. Additionally, this approach in testing enhances collaboration among developers, testers, and other stakeholders. By working closely from the beginning, these teams foster better communication and understanding, which contributes to a smoother software development process (more on the benefits below).

Shift left testing begins by integrating QA (Quality Assurance) processes at the very start of the Software Development Life Cycle (SDLC). QA engineers are involved in initial requirement analysis and design discussions. They conduct static testing techniques such as requirement reviews and design inspections to identify potential issues before any code is written.

Once development begins, Continuous Integration (CI) and Continuous Testing (CT) practices are implemented. In a CI environment, developers frequently commit code changes to a shared repository. Each commit triggers an automated build process that includes running a suite of unit tests, integration tests, and other automated tests. This CI pipeline ensures that code changes are continuously validated, catching issues as they are introduced. 

Shift left testing promotes collaboration through Agile and DevOps methodologies. Cross-functional teams consisting of developers, QA engineers, and operations personnel work together from the beginning. Practices like pair programming, code reviews, and test-driven development (TDD) are implemented to enhance code quality and ensure that testing considerations are included in the software development process.

For example, here is a rough workflow of shift left testing:

1. Requirement gathering

At this stage, testers join the initial meetings to understand the requirements and start identifying potential test cases.

2. Design phase

Testers review design documents and provide feedback on potential issues and testability concerns. Besides, test plans and test cases are developed based on the design.

3. Development phase

Developers write code and integrate it into the main codebase regularly. Then automated tests run continuously to validate code changes.

4. Continuous feedback

Test results provide continuous feedback to developers, allowing for quick adjustments and improvements.

Remember: It’s important to organize regular stand-up meetings and collaborative sessions with stakeholders to ensure alignment and address any emerging issues promptly.

5. Final testing and release

By the time the final testing phase is reached, most issues have already been identified and resolved. Final testing ensures that the product is stable and ready for release with minimal defects.

Shift left testing is all about:

1. Early testers involvement

Engaging testers from the start ensures that potential issues are identified before they can affect later stages of software development. This proactive involvement is crucial for preventing defects.

• Inclusion from the start: testers are involved from the initial stages of the development process, such as requirements gathering and design.
• Requirement review: testers review requirements and design documents to identify potential issues early on.
• Preventative mindset: the focus is on preventing defects rather than just detecting them. 

2. Continuous integration and continuous testing

Implementing continuous integration and testing practices allows for ongoing validation of code, ensuring that each change is tested as soon as it’s made. This method aids in sustaining code quality across the entire development lifecycle.

• Frequent testing: testing is conducted continuously throughout the development cycle, not just at the end.
• Automated testing: automated tools are used to run tests regularly, ensuring that code changes are validated quickly.
• Immediate feedback: developers receive rapid feedback on their code, allowing for quick fixes and adjustments.

3. Collaborative development

It promotes early collaboration among developers, testers, and stakeholders, fostering improved communication and alignment on project objectives right from the start. This collaborative approach ensures a cohesive team effort and a clear focus on common goals throughout the project lifecycle.

• Cross-functional teams: developers, testers, and other stakeholders work together closely from the beginning.
• Shared responsibilities: testing is seen as a shared responsibility, not just the domain of the QA team.
• Better communication: enhanced collaboration leads to better communication and understanding of project goals. 

4. Shift in testing culture

Adopting a shift left approach requires a cultural shift towards prioritizing quality and continuous improvement. This change in mindset fosters a proactive approach to quality assurance.

• Quality mindset: there is a cultural shift towards quality, with everyone involved prioritizing testing and quality assurance.
• Proactive approach: teams adopt a proactive approach to identify and address issues before they become significant problems.
• Continuous improvement: the process involves constant evaluation and improvement of testing practices.

5. Use of modern tools and practices

Leveraging modern tools and practices like Agile, DevOps, and test-driven development helps integrate testing seamlessly into the development process. These practices support iterative development and continuous delivery.

• Agile and DevOps: shift left testing is often integrated with Agile and DevOps practices, promoting iterative development and continuous delivery.
• Test-driven development (TDD): practices like TDD are adopted, where tests are written before code, ensuring that functionality is verified from the outset.
• Behavior-driven development (BDD): it utilizes a language that bridges the gap between technical developers and non-technical stakeholders, promoting enhanced collaboration through accessible test creation.

As the lead of your development team or a business process owner, you understand the challenges of delivering high-quality software on time. The benefits of shift left testing can provide the solutions you need. By integrating testing earlier in your development process, you can catch issues before they escalate, save valuable time and resources, and foster a more collaborative environment. What are the key benefits of shift left testing?

1. Cost efficiency

It significantly reduces the cost of fixing defects. By identifying and addressing issues early in the software development process, you avoid the exponential costs associated with late-stage bug fixes.

This proactive approach minimizes rework, reduces resource expenditure, and ultimately saves your organization money.

2. Enhanced product quality

Early and continuous testing ensures higher product quality. By involving QA from the start and integrating automated testing into the development pipeline, defects are detected and resolved swiftly.

This leads to a more robust and reliable product, reducing the risk of post-release issues that could harm your reputation. 

3. Faster time-to-market

This testing method accelerates the development cycle. Continuous integration and testing streamline the development process, allowing for quicker iterations and faster delivery.

This agility enables your team to meet tight deadlines, respond to market demands promptly, and gain a competitive edge.

4. Improved collaboration

It fosters a collaborative culture. By involving QA, developers, and other stakeholders early on, communication and alignment improve.

This collaboration enhances team synergy, reduces misunderstandings, and ensures everyone is on the same page, leading to a more cohesive and efficient development process. 

5. Predictable development cycle

With continuous testing and early defect detection, your development cycle becomes more predictable. Issues are identified and resolved early, reducing the likelihood of last-minute surprises and delays.

This predictability enhances planning accuracy and allows for better resource allocation.

6. Increased customer satisfaction

Delivering a high-quality product on time directly impacts customer satisfaction. By implementing Shift left testing, you ensure that your product meets customer expectations and functions reliably from day one. Satisfied customers are inclined to return and promote your brand to others.

7. Empowered teams

Shift left testing promotes a quality-first mindset across your organization. Team members feel more accountable and empowered to deliver high-quality work.

This cultural shift towards quality fosters a sense of ownership and pride, motivating your team to strive for excellence.

8. Continuous improvement

The continuous feedback loop inherent in shift left testing drives ongoing improvement. Regularly analyzing test results and performance metrics helps identify areas for enhancement. This iterative approach ensures your development practices evolve and improve, keeping your organization at the forefront of industry standards.

• Quality assurance is integrated from the beginning of the project, ensuring potential issues are identified and addressed early.
• Code changes are regularly integrated and tested continuously, allowing for immediate detection and resolution of issues.
• Automated tests are used to ensure thorough and consistent testing, saving time and reducing human error.
• Throughout the project, developers, QA engineers, and other stakeholders collaborate closely, fostering improved communication and ensuring everyone is aligned.
• Testing is conducted proactively, with tests written before code to ensure that all functionality is verified from the start.
• Automated tools are used to review code and identify potential problems early in the development process.
• Real-time feedback on the status and quality of the project is provided, allowing teams to make quick adjustments as needed.
• Emphasizes a culture where everyone is responsible for quality, promoting early identification and resolution of issues. 

By adopting shift left testing, you can achieve cost efficiency, enhanced product quality, faster time-to-market, improved collaboration, a predictable development cycle, increased customer satisfaction, empowered teams, and continuous improvement. The benefits of shift left testing collectively contribute to the success and competitiveness of your organization.