Shift Left Testing: Make It Work in the Real World

Theory matters, but results matter more. See how shift left testing works in practice, and why pairing it with shift-right can take your quality further.

Why should you use shift-left testing? With Agile practices and DevOps becoming a norm, shift-left has emerged as a powerful way to rethink the role of testing, placing it earlier in the process and turning it into a driver of collaboration, speed, and smarter decision-making. It’s how QA stops being a final check and starts being a continuous presence throughout the software development process.

This shift changes more than timing; it redefines how we look at testing. Instead of traditional Quality Assurance (QA), it becomes QE: Quality Engineering, where quality is owned by the entire team and built in from the very beginning.

In this guide, we’ll walk you through the key concepts and benefits of shift left software testing, and how to approach it effectively in real-world scenarios. We’ll also explore how combining it with shift-right testing can strengthen feedback loops, reduce risk, and support a continuous, adaptive quality strategy.

Want to move from theory to impact?
Explore our end-to-end software testing services!
Let’s talk about what shift-left means when it becomes part of your work.

What is The Shift-left Testing Approach?

The shift-left testing approach involves moving testing activities to the earlier stages of the software development cycle. Instead of waiting until the end to test, shift left focuses on enabling development and testing teams to collaborate from the start to identify and fix issues as early as possible. This improves software quality and reduces costs and development time.

To truly excel and advance today, a tester must not only be great at testing but also be an engineer of the agile testing process. This means working together with development and operations teams and analyzing quality during every stage of development, as shown in the graphic below.

For instance, testers have to jump in and take a more proactive role even before development starts by being present during the gathering of requirements.

What’s the Difference Between Shift-Left and Shift Right Testing?

Put simply, the difference lies in when the testing happens and why. While the shift-left strategy aims to prevent issues early, the shift-right strategy focuses on learning from real user behavior once the software is live.

The image above helps illustrate a key shift in how we think about testing. For a long time, testing was something that happened near the end, once everything was built. The shift-left approach turns that idea on its head. It brings testing into the earliest stages of development, so that we can prevent issues before they even happen.

Now, you might be wondering: what about testing that happens after release? That’s where shift-right testing comes in. Instead of focusing on prevention, shift right is all about observation: seeing how the system behaves in the real world, under real conditions. It includes things like monitoring, A/B testing, chaos engineering, and collecting feedback directly from users.

Why It’s Worth Combining Both

Although this article puts the spotlight on shift-left testing, especially because of its impact on catching bugs early and making collaboration more fluid, we believe in looking at the full picture. Relying on just one approach can leave blind spots.

That’s why combining shift-left with the shift-right approach is so powerful. It lets teams build quality from the start and continue refining it once the software is live. Together, they support a continuous testing mindset that stretches across the entire development lifecycle.

If you’re curious about how to bring both sides together, we invite you to explore this article.

Key Activities for Testers in Shift-left Testing

Here are some of the crucial tasks testers take on in a shift-left approach:

Helping developers implement unit testing: Testers collaborate with developers to create and run unit tests, verifying that individual components work correctly from the get-go.
Planning, creating, and executing integration test cases: Testers focus on writing test cases and executing them to check how different parts of the system interact, catching issues early in the integration phase.
Automating tests: Testers deploy automated tests to make the testing process faster and more reliable. By integrating automated unit tests as part of this approach and adding more unit tests as well as API and GUI tests where necessary, they can achieve greater coverage and identify issues earlier within the development workflow.
Employing virtualized services at every stage and component level: By using virtualized services at every stage and component level, testers can simulate different parts of the system, making it easier to test components in isolation and in various scenarios.
Gathering, prioritizing, and processing feedback: Testers collect feedback from various stages of development, prioritize it based on impact, and address it promptly. This contributes to a loop of continuous feedback that helps guide product quality throughout the lifecycle.
Applying the testing pyramid model: Structure your test suite with a broad base of automated unit tests, a smaller set of integration tests, and a minimal layer of end-to-end tests. This distribution promotes faster feedback cycles and greater test stability as teams shift left.

Process Changes During the Shift

Shifting left also brings about some significant process changes:

Frequent code integration: Rather than waiting weeks to add code to that of the rest of the team, integrate code every day, or even several times a day, to catch issues early.
Continuous quality analysis: Instead of detecting problems at the end, continuously analyze quality as development progresses to address issues early and maintain steady product quality.
Considering a static code analyzer: While not mandatory, using these tools can be helpful to detect vulnerabilities, syntax issues, and logic flaws early in development, without executing the code. It’s a valuable addition to dynamic testing efforts and can enhance code quality when applied appropriately.
Integrating security scanning tools: Tools like Static Application Security Testing (SAST) and Dynamic Application Security Testing (DAST) can help identify vulnerabilities early in the pipeline. While not required in every context, they’re a valuable option for embedding security checks into the development cycle.
Early involvement of testers: Get testers involved from the very beginning, even during the requirements gathering phase, to identify potential issues early.
Collaborative development: Foster a culture of collaboration between developers, testers, and operations and make quality a shared responsibility throughout the development process.

What is the Role of Shift-Left Testing in Software Development?

The main role of shift-left testing is to detect and fix errors as early as possible in the development cycle. It’s all about testing early, from the very beginning, so development teams can fix defects sooner and avoid costly delays later in the cycle.

By involving testers from the outset, design, and testing requirements, teams can identify code changes and code issues before they become major headaches. The result? A more robust test process and fewer unpleasant surprises at the end of the project.

er unpleasant surprises at the end of the project.

Revolutionize Your Testing with our AI-powered assistant Abstracta Copilot!
Book a meeting and talk with our experts about how we can support you.

Why Make the Shift if You Haven’t Yet?

Benefits of Shift Left Testing

Reduced costs
Increased efficiency and quality
Gaining a competitive edge
Faster time to market
Stronger collaboration across teams
Earlier risk mitigation

To unlock these benefits, it’s important to implement shift left testing in a thoughtful and structured way. Here’s a breakdown of what each benefit involves.

1. Reducing the Cost of Testing & Development

It is still true what Larry Smith said over 20 years ago when the “shift-left” concept was first introduced: “Bugs are cheap when caught young.”

One of the aims of Agile testing is early bug detection, to identify errors as soon as possible. What we mean by as soon as possible is: as soon after the exact moment in which the error was inserted into the system.

When you test with every build (especially during unit testing), you may find smaller errors that are easier to detect, locate, and fix at a lower cost.

Maintaining quality as you go also leads to cost savings by mitigating the tremendous costs and unnecessary work of going back and re-doing certain things.

Want to know how much money you can save with test automation? Check out this post on the ROI of test automation.

2. Increasing Efficiency & Quality

We often find that the increased levels of automation when shifting left allow for better test coverage, as well as:

Increasing test coverage by running more tests in the same amount of time
Freeing up time for testers to focus on more challenging and rewarding tasks
Reducing human error
Monitoring performance over time
Code quality checks
Built-in security checks
Reducing issues in production (that users will face)

Beyond these benefits, being able to start testing sooner invariably results in more quality, as testers are no longer rushing to find all the errors at the end. This requires adopting a shift left mindset, where quality is owned collectively and considered from day one.

3. Gaining a Competitive Edge

Shifting left your QA gives you a competitive edge in two ways: you can speed up time to market and attract top talent.

About staying competitive in today’s ever-changing technological landscape, Alon Girmonsky, founder of BlazeMeter, said it best:

“Today, the barrier to compete is minimal, and the only way to defend one’s stature is by innovating in short iterations… meaning adopting Agile.” – Alon Girmonsky

As we can all agree that it is important to deliver software more quickly, it also shouldn’t be rushed out the door. Shift-left testing answers the problem of accelerating development without sacrificing quality, leading to higher customer satisfaction with each release.

Ultimately, delivering high-quality software faster and more efficiently is what allows teams to stand out and consistently deliver a product that exceeds customer expectations.

4. Accelerating Time to Market

The pressure to release faster is real, but doing so without the necessary checks often leads to setbacks that cost more than a delayed sprint. Shift-left testing helps teams move quickly without sacrificing stability. By catching defects early, validating assumptions sooner, and integrating quality from the start, teams can deliver functionality with fewer surprises and less rework, minimizing late-stage bottlenecks.

5. Encouraging Stronger Collaboration

One of the most meaningful shifts doesn’t come from new tools but from new conversations. When quality is part of the conversation from day one, QA, Dev, and Product stop working in isolation and start co-creating. This leads to sharper definitions, fewer misunderstandings, and stronger outcomes. Shift-left testing invites QA to help shape the work, not just validate it. And when collaboration starts earlier, the entire development process becomes smoother, more thoughtful, and more aligned with user needs.

6. Identifying Risks Sooner

The later you discover a critical issue, the harder it is to solve. Shift-left testing allows teams to identify risks before they escalate, from code vulnerabilities to performance bottlenecks to misaligned expectations. By integrating testing into early design and planning stages, you gain visibility into what might go wrong while you still have time to course-correct. This helps build confidence across the team, making releases less stressful and more predictable.

When Shift-Left Testing Doesn’t Work

Maybe you have already heard all of those benefits, but you are STILL not convinced about shift-left testing for this reason: you’ve seen that even Agile teams can face the same bottlenecks as seen in Waterfall.

For example, as Shridhar Mittal, former GM of Application Delivery at CA Technologies, explains, “Due to the complexity of environments and composite applications, Agile teams are often stuck waiting in a queue once all of the pieces come together in the performance and user acceptance testing phases.”

The solution he provides that we agree with is utilizing service virtualization. Service virtualization emulates the behavior of essential components that will be present in production, enabling integration tests to take place much earlier during the development phase of each sprint. This is how you can eliminate that key bottleneck, while also benefiting from eliminating errors earlier on.

Along with service virtualization, you have several tools to set up your automated systems and continuous integration, such as Jenkins, CruiseControl, Bamboo, and TeamCity, which all have web management interfaces. Or, you could go with a cloud solution like Amazon Pipeline Code, TravisCI, CircleCI, Codeship, and Microsoft’s Visual Studio Team Services.

One Important Note

Just having these tools in place does not ensure a successful shift and does not imply quality engineering. There are several preconditions and a level of testing maturity that must be reached in order to achieve Continuous / Agile / Shift-left testing.

For example, a precondition for test automation would be having the appropriate test environments and test data set up. Without this and several other preconditions, your shifting of QA to the left will be problematic, at the least.

Is your team ready to shift left?
Try our 9-question assessment to find out how your testing stacks up and get custom tips for your software testing strategy.
Take our software testing maturity assessment!

Wrapping Up

With Agile now the standard, it’s essential to adopt shift-left testing as a key strategy to increase quality, boost efficiency, reduce costs and risks, and stay competitive.

Shift-left testing isn’t about focusing on a testing phase. It’s about running software tests from the very beginning, embedding testing early, and also maintaining it in later stages and throughout the whole development lifecycle. This approach emphasizes early unit and integration testing, along with automating tests where possible, to identify issues sooner.

Complementing shift-left with continuous testing and shift-right testing (meaning testing in production) further enhances this strategy, supporting continuous improvement and helping teams deliver high-quality software at a faster pace.

FAQs about Shift Left Testing

What Are The Four Types of Shift-Left Testing?

The four types of shift-left testing include traditional shift-left testing, incremental shift-left testing, Agile/DevOps, and model-based testing.

Traditional testing: Moves functional testing to the early stages, catching issues right from the start and saving time and money down the line.
Incremental testing: Integrates testing into each development increment, so every new feature gets tested immediately, maintaining high quality at every step.
Agile/DevOps: Combines agile and DevOps practices for continuous testing throughout the development process. It’s like having a built-in safety net that keeps everything running smoothly as you go.
Model-based testing: Uses models to design and run tests, catching design errors early. Think of it as having a detailed map that guides you to build everything correctly from the ground up.

What Is The Difference Between Shift-left and TDD?

Shift-left and TDD (Test-Driven Development) are complementary but distinct approaches. Shift-left is a general philosophy advocating for testing as early as possible in the development cycle. In contrast, TDD involves writing tests before the production code. In TDD, tests guide the development of the software. Shift-left, however, is broader and includes various practices and types of testing.

What Is Shift Right Testing?

Shift right testing refers to testing done in production environments to observe real user behavior and system performance. It includes practices like A/B testing, monitoring, and canary releases, helping teams validate quality after deployment and drive improvements based on real-world data.

What Is The Difference Between TDD and Shift-Right?

TDD (Test-Driven Development) and shift-right are also are also distinct strategies. TDD focuses on writing tests before the production code to guide software development. Shift-right, on the other hand, emphasizes testing and monitoring in the production environment. While TDD aims to catch issues early in the development process, shift-right focuses on boosting quality and performance in the live environment, often using techniques like A/B testing, canary releases, and real-time monitoring.

What is Shift Left Security Testing?

Shift-left security testing integrates security checks and practices earlier in the development lifecycle. This proactive approach helps identify vulnerabilities at the design and development stages, reducing risks and improving the overall security posture of the software.

What Is Shift Left with Example?

In an Agile context, shift-left means involving testing from the very beginning. For example, during sprint planning, a tester works with developers and product owners to review user stories, define testing requirements, and identify potential edge cases. As developers write code, they also create unit tests, while the tester simultaneously designs automated integration tests. By the end of the sprint, all features are tested continuously, reducing the risk of last-minute surprises.

How We Can Help You

With over 16 years of experience and a global presence, Abstracta is a leading technology solutions company with offices in the United States, Chile, Colombia, and Uruguay. We specialize in software development, AI-driven innovations & copilots, and end-to-end software testing services.

Our expertise spans across industries. We believe that actively bonding ties propels us further. That’s why we’ve forged robust partnerships with industry leaders like Microsoft, Datadog, Tricentis, Perforce BlazeMeter, and Saucelabs, empowering us to incorporate cutting-edge technologies.

Testing Maturity Model

Our software testing maturity model is a comprehensive framework that helps teams improve the quality of their software testing efforts, including all types of software testing. This model emphasizes the importance of a well-constructed test environment and the use of reliable testing tools to meet the needs of users and stakeholders.

Processes, Technology, and People

Effective processes and tools are crucial, but they must also align with the skills and capabilities of your team members. Our approach allows us to create a well-rounded, adaptable test plan that fosters active participation and effectively meets test deliverables.

Our holistic approach enables us to support you across the entire software development life cycle.

Visit our Test Strategy Services page and contact us to grow your business!

Follow us on Linkedin & X to be part of our community!

Blog

Shift Left Testing: Make It Work in the Real World

What is The Shift-left Testing Approach?