Shift-Left Testing: A Testing Methodology to Maximize Efficiency  

Shift-Left Testing

The testing landscape has witnessed a lot of advancements over time to satisfy the increasing demands for high-quality software. In today’s agile world, organizations strive to meet the demands of faster deployment cycles and evolving user requirements. As a result, they explore new methodologies to evaluate an application’s functionality, reliability, and quality. 

Shift left testing is one such methodology that enables organizations to release their products early to the market with proper quality checks. In this article, we will walk you through shift left testing in agile environment and its benefits and implementation. 

What is Shift Left Testing? 

shift left testinf

The shift left testing approach is a testing methodology that emphasizes conducting testing activities at the early stages of the development process. It primarily focuses on three aspects – accelerating the testing process, uncovering and addressing bugs or errors in the early phases, and improving the quality of code.  

In the traditional development models, the testing activities are generally carried out after the entire development of the software, i.e., at the end. These models are typically linear or sequential in nature, where the testing phase starts only after code development. 

However, this is not the case with shift left testing. In this approach, the development and testing phases take place concurrently. As soon as developers write a unit of code, testers run tests to validate its functionality before pushing it to version control. Even if code behaves unexpectedly, developers can fix it quickly. Shift left testing usually promotes “test early and often“. It removes a large number of bugs as early as possible before moving code into the production phase and reduces time to market.

Why Do You Need Shift-Left Testing? 

why go for shift-left testing

Consider any of the traditional software development models, say the waterfall model. It is one of the oldest SDLC models, and it is used very rarely today. It is a linear sequential life cycle model, wherein the next phase starts only after the execution of the current phase. Have a look at the phases of the waterfall model. 

6 Phases of the Waterfall Model 

A simple waterfall model has 6 phases: Requirement Analysis → Feasibility Study → Architectural Design → Software Development → Testing → Deployment

You can see that the testing phase is at the extreme right of the development cycle. At this point, the software is fully developed. So, if the testing team discovers any errors or bugs, it becomes challenging to go back to previous phases and make modifications. However, doing this disrupts the entire life cycle and requires significant rework.  

The consequences of this approach are: 

  •  A significant increase in cost for rework from scratch
  • An increase in time to market, as the rework consumes a lot of time.

As a result, organizations today adopt the shift left approach. Here, the testing is literally pushed to the left of the development life cycle, i.e., at the beginning of the pipeline. The testing team can uncover and rectify bugs and errors often and in the early stages of development. This significantly saves the time, effort, and cost required to fix those bugs in the later stages of development. 

Benefits of Shift Left Testing 

The following are some noteworthy benefits of shift left testing: 

1. Early Bug Detection 

Shift left testing incorporates testing activities in the initiation phase of development. Hence, testers can identify bugs early before propagating them in the later stages of development. This makes it easy for developers to fix bugs quickly and prevent compound errors. Plus, early bug detection facilitates debugging and ultimately reduces time and effort for maintenance. 

2. Cost Saving 

Fixing bugs in the later stages of development or post-production is extremely costly and time-consuming. Shift left testing mitigates those costs and saves time by enabling testers to discover bugs early in the SDLC, as they are less complex to rectify. Moreover, organizations can save a lot by avoiding potential rework, unlike traditional development models.  

3. Accelerated Time to Market 

Shift left testing accelerates the development process and the application’s time to market. As development and testing go hand in hand, the development process maintains a steady pace. There are no delays caused due to bug-fixing cycles or unexpected events in the later stages of development. As a result, organizations can bring products to the market faster. 

4. Enhanced Collaboration 

Shift left testing strongly emphasizes collaboration between cross-functional teams, including developers, testers, and stakeholders. With the involvement of testers early in the development process, developers gain insights into potential challenges and risks, allowing them to create a robust preventive strategy. This collaborative approach improves the quality of the software and fosters a culture of teamwork within an organization. 

5. Improved Product Quality 

Iterative and continuous testing throughout the SDLC ensures the high quality of the software. Issues are identified and fixed at every stage of development. Also, teams focus on validating the software’s functionality and ensuring that the final product meets specified requirements.  This leads to improved software quality, increased reliability, and maximized customer satisfaction.

How to Implement Shift Left Testing? 

Here are some practices to help you implement shift left testing in your development process: 

1. Introduce Testers In Planning and Analysis Phase  

By introducing testers in the planning and analysis phase, the development team can receive feedback on the software design’s testing feasibility and input on potential testing scenarios. Testers can pinpoint any ambiguous requirements, missing requirements, and inconsistencies that may slow down the development process. 

In addition, testers can help developers in writing code by keeping testability in mind. This means testers can specify when developers should create the software module’s mocks and substitutions for testing if a certain module is not ready.   

2. Specify Quality Standards 

Before integrating testing activities into development, it is essential for both teams to understand the tech infrastructure, cutting-edge testing practices, and each team’s technical capabilities. Additionally, this integration requires setting clear expectations and quality standards to achieve high-quality code. Both development and testing teams prioritize expectations and standards and deliver high-quality software products effectively.

3. Adopt BDD Testing 

BDD stands for Behavior Driven Development. BDD testing refers to an Agile approach to software testing wherein testers write test cases in a simple language, enabling non-technical to understand them easily. The primary goal of BDD testing is to facilitate collaboration between developers, testers, stakeholders, and business analysts by focusing on the software’s behavior rather than its implementation. 

As BDD encourages collaboration between cross-functional teams, it naturally fits into the shift left testing approach. Also, the ubiquitous language of BDD enables managers to understand what happens throughout the software development process. 

4. Adopt Automation Testing 

Utilizing test automation tools in the shift left testing approach significantly reduces the pressure on the testing team. Also, these tools facilitate the testing process and accelerate the development life cycle, reducing the software’s time to market. 

Why Use Real Devices for Shift Left Testing? 

For accurate results, testing on real devices is highly recommended. By running tests on simulators or emulators, it is not possible to evaluate the quality of the code adequately and get entirely correct results. Hence, development activities based on these results may not lead to high-quality software. 

Conducting tests on real devices from the beginning of the development process prevents bugs and ensures error-free, comprehensive testing. 

TestGrid’s Real Device Cloud provides access to a combination of real devices and browsers to help users evaluate their apps and websites on the cloud from anywhere. Users can simulate real user conditions, such as low network and battery, changes in geolocation, screen resolutions, etc. 


Shift left testing is a go-to testing methodology in this era of increasing demands for a faster development lifecycle. By integrating testing into development, shift left testing empowers organizations to identify and fix bugs early in the development process and save significant time, effort, and cost required to fix them in the later stages. 

At TestGrid, we believe in the power of this approach. Our tools are designed to amplify the benefits of shift-left testing, enabling you to deliver exceptional experiences to your users.