End-to-end guide on Shift left testing


Traditionally in application development models, the testing phase was used to be done on the extreme right or at the very end of the application development lifecycle which is too late. Hence resolving them towards the extreme right and at the end requires enormous effort, cost and time. Shift left testing also reduces the number of defects that make their way into production software. The idea is to shift from manual to automated testing so that by the time manual testing is needed, there is less work to be done. 

To avoid this situation and improve the application’s development process, organizations, later on, realize the impact of keeping the Testing Phase on the extreme right of the application development phase. And then comes the implementation of shift left testing as the proposed solution.

In this article, we are going to learn about an end-to-end guide on shift-left testing. This will include what shift left means, its importance, benefits and how you can adopt this approach in your organization. Now let’s have a look at how to achieve zero bugs during the deployment phase.

To avoid approaches where testing is only carried out at the very end of the application development life cycle. Then the shifting left concept emerges, which introduces moving the testing phase in the early stages of application development that is to the Left from the Right. 

Shifting left is bringing development and testing together thereby resulting in faster and earlier testing. Testing early and often reduces the number of defects and defects that are caught early cost less and increase the quality of the code.

The aim of the shift-left approach is to identify and resolve bugs as early as possible to improve application quality and reduce time spent resolving issues in earlier stages of the application development lifecycle.

Why Is It Called A Shift To The Left?

In representing sequential phases of anything, the earliest or the starting phase is at the extreme left, and then the progression from that is towards the extreme right or at the end. Taking this concept shift left testing refers to bringing the testing stage earlier in the development life cycle. Shift left takes care of issues when they arise and ensures fewer flaws in a later stage.

However, don’t think that shift-left testing only means testing placed at the starting phase of development, instead of at its end. Shift left testing is a continuous activity occurring in short, repetitive cycles which means  “test often rather than just testing in the end and start as early as possible.

Importance of shift left testing strategy

We often underestimate the effects of testing early on in the application development life cycle as the agile methodology describes. Regularly testing code with each code increment helps to guarantee the quality of the project but also saves you a lot of time and money.

Most bugs enter the code during the coding phase and when the testing phase comes after the coding phase, many bugs get identified during the testing phase. This means a lot of bugs have to be fixed. This is quite challenging because all the codes have already been written and the only way to fix the problem will be to write the code again. As a result, a lot of time and money will have to be invested to resolve the issue and the time to market lengthens significantly.

The sooner the bugs get fixed, the better. The easiest bugs to correct are those that get identified during the time of writing or reviewing code because at this stage these code blocks are small and easy to manage. Here comes the importance of introducing Shift left testing that allows the developers to quickly and frequently identify and resolve bugs. And bring in a guaranteed quality application by saving a lot of time and money.

Benefits of a Shift Left Testing approach

Implementation of the shift left testing approach, helps the organizations to put quality at the top of their priority list and work to uncover issues as early as possible. Some of the significant benefits of shifting left are-

  • Efficient and higher quality application as the code contains fewer or no bugs.
  • Reduced testing time by preventing doing extra work or going back and redoing everything.
  • Saves a lot of time in solving issues by detecting them early.
  • Allows to automate testing more effectively with less human error and increases coverage by conducting multiple tests at the same time.

How to plan shift left testing strategy

Here are some of the things you can do to shift your application testing to the left:

Demand Planning

Demand planning is an integral part of the shift-left strategy. It enables the testers to obtain a better understanding of future demand by collaborating with the management. It provides a starting point for all activities in the test lifecycle, like planning and confirming the budget, resource allocation, and testing strategies beforehand with this insight.

Static Testing

Static testing is done in an early stage and includes design and requirements of validation. The purpose of static testing is to find defects early in the life cycle before they become very expensive to fix.

Unified testing strategy

This is an overall, high-level approach for end-to-end testing, from unit testing to user acceptance testing (UAT), operational readiness testing (ORT), and post-deployment testing. This strategy covers all phases of quality control, defining all QA responsibilities.

A unified test strategy evaluates dependencies on environments, stubs, automation, and test data guaranteeing that the respective teams can fulfill the requirements.

Risk-based analysis

This strategy helps to determine and analyze the consequences and probability of failure for every test scenario. using this method functional, non-functional, and regression testing can be performed.

How to practice the Shift Left Testing Approach in your organization

Shift left testing can be implemented in your organization by following these few simple steps.

Coding Standards

A better place to start is by establishing code standards for your development team. The development team needs to have the same understanding of the project. It allows them to review code more quickly and ensures a higher quality of code. Coding standards help in preventing incorrect or unsafe code, hence reducing the frequency of errors.

Implementing testing in the early stages of development

The first thing to figure out is which tools can be helpful for your codebase as a group. Apart from that, the team should consider how testing can be integrated into an early stage of the development lifecycle. One adaptable strategy is the agile method, which works with tiny code increments known as sprints.

However, for some organizations switching towards the agile approach is not easy. As a result, the development team may agree on building unit tests for every new feature. As individual code units are easier to test because they are smaller and more navigable. Later, write integration tests for these different bits of code to ensure that they work seamlessly together.

Adopt Test Automation

Test automation speeds up the development life cycle. It ensures fewer bugs in the later stage of development and enables you to reduce the time to market.

As shift left testing requires frequent testing, it is good for the development team to embrace the test automation tool. Besides conducting automating for each code increment in addition to the release of every new build.

This will relieve the load on the testing team’s responsibilities and provide faster feedback about the stability of the code.

With test automation, you can profit from the most extreme advantage of Shift Left testing, but it is difficult to manage the automation suite and your own infrastructure of real devices. So it is best to perform your automation tests on a cloud-based testing infrastructure. 

To ease your task, a platform like LambdaTest is there to provide you with a cloud of more than 3000 real devices, browsers, and operating systems with their respective versions. You can get their access to testing from anywhere across the globe at any time. The benefit of using LambdaTest is it allows you to write test cases right from the design phase. 

LambdaTest is an automation testing tool that supports the Shift Left approach. It is a secure, reliable, scalable cross-browser testing platform that helps you to perform end to end testing with higher test coverage and lesser built times. It also lets you perform parallel test execution where you can prioritize and schedule tests in multiple environments. And enables you to capture full-page screenshots so that you can log the error and debug quickly.

Introduce testers to coding:

Basic coding skills help testers to implement some quick fixes wherever possible. This enables them to be effective at code reviews and to be valuable contributors to teams. They need to be proficient enough to be able to read and modify simple code like an automated test or able to rework fundamental methods.


Initially focus for Testing was only on Defect Detection and now with Shift Left Testing focus has shifted to  Early Defect Detection. If you are trying to shift to the left, then remember to keep the above-shared information in your mind before you start. They can help you to achieve the goal of delivering a higher quality application with greater efficiency in no time.

Leave a Reply

Your email address will not be published. Required fields are marked *