Shift left testing is an essential and popular technology practice. Shift left testing involves testing in the software development lifecycle (SDLC) as early as possible. Shift left testing can also be conceptualized as shifting tasks related to testing to the left on a linear software development timeline.
Shift left testing is beneficial because it is challenging to fix issues when they are discovered later, or further right, in the software development lifecycle. However, it is essential to note that shift right testing also offers distinct advantages. To learn more about shift left vs. shift right testing, see this guide.
In the context of shift left testing, “testing” is an experiment to assess the functionality and execution of a software solution and ensure it meets customer requirements. Four different approaches to shift left testing are traditional, incremental, Agile/DevOps, and model-based. Each system builds upon the others and offers distinct advantages and disadvantages.
This guide explains four shift left testing approaches.
1. Traditional Shift Left Testing
Traditional shift left testing is a widely practiced and mostly standardized approach that is an accessible starting point for companies looking to improve their software. Using the SDLC V-Model, traditional shift left testing happens early in the development lifecycle, so issues can be identified and resolved early on, saving time and money.
Traditional shift left testing focuses on unit and integration testing, which developers perform. It addresses the emphasis on user interface (UI) based systems and acceptance testing, which is managed by testers. It can be automated using Selenium browser automation and API testing, and, for best results, it is commonly combined with other quality assurance (QA) processes such as continuous integration and continuous delivery (CI/CD).
2. Incremental Shift Left Testing
Incremental shift left testing is also a widely practiced and mostly standardized approach to software testing. Like traditional shift left testing, incremental shift left testing also moves testing activities up in the development process, but it differs in that the testing activities are implemented gradually. First, the testing activities are moved to the coding phase, and then they are incrementally added further left to earlier stages like requirement gathering and design.
This approach is suitable for testing large complex systems that are software-heavy because many projects that involve large and complex software-heavy systems naturally break development down into increments. Incremental shift left testing takes place in each subset of development and moves both developmental testing and operational testing earlier in the development lifecycle.
3. Agile/DevOps Shift Left Testing
Agile/DevOps shift left testing is a popular approach to software testing that also moves testing earlier in the development process. This approach is popular with Agile and DevOps professionals because it enables frequent testing early during the development phase. It differs from traditional and incremental shift left testing approaches in that it involves many quick subsets of development, also referred to as sprints.
In Agile/DevOps, testing occurs in each sprint, a short time frame in which a team works on a specific feature. Agile/DevOps shift left testing typically includes developmental testing and excludes operational testing. This means that developers, not testers, perform testing. The focus is on ensuring that the code satisfies requirements instead of assessing whether or not the software meets performance standards.
4. Model-Based Shift Left Testing
Akin to the other three approaches, model-based shift left testing also moves the testing earlier in the software development process. Model-based shift left testing is distinct because it tests the software before it exists as code. In fact, it involves testing executable requirements, architecture, and design models.
In model-based shift left testing, testing can begin almost immediately, as soon as the software is conceptualized. This is key because many issues are introduced in the requirement-gathering phase. When caught early on, companies can save money and time, improve software quality, and increase the efficiency of the software development process.
Shift Left Testing with Encora
Encora software engineers are highly skilled at all aspects of and approaches to shift-left testing, including traditional, incremental, Agile/DevOps, and model-based. Encora can guide companies to the best approach for their objectives and applications. We can help companies streamline and enhance their testing process and reduce the risk of failed products with automated testing earlier in the SDLC. The team of expert engineers offers the benefits of their unique skill sets to assist our clients wherever they are applying shift-left testing. Contact Encora to get started with shift left testing.
